An axe to grind, Pg.1

AN AXE TO GRIND. MTOA’s QUARTERLY MAGAZINE

An axe to grind, Pg.2

Chairman's stump 4

A Blustery Day 10

Hedging Your Bets 12

Water Water Everywhere 14

BS 8545 22

Tree Risk Systems 32

Tongues of Fire 38

What is the Urban Forest? 42

Trees and Climate Change 46

Ride for Research 52

And finally 55

Inside this issue:

Front cover picture. Failed Populus italica Brunswick Park, Sandwell.

An axe to grind, Pg.3 New look Axe.

Interactive content; where you see the leaf logo then the page is ”live” so click for any internet content, try it

Chris Parker Glynn Percival Kenton Rogers Moray Simpson

Meet this edition’s contributors

If you click on any of the pictures you can read there on-line bio.

Ian McDermott

Editor

If you are reading this edition of the Axe on PDF then please ensure you have the view option set for a two page spread, it is designed for on-line

viewing so make use of the links embedded.

The MTOA is a fully constituted not for profit organisation . The views expressed in the magazine may not reflect the official views of the MTOA

and the association accepts no liability for any views or technical advice presented by its contributing authors.

Jeremy Barrell Mark Dunteman Francesco Ferrini Jonathon Mills

An axe to grind, Pg.4 Upcoming

Events.

May

ISA European con-

gress

June

TRAQ Course

MTOA Quarterly

meeting, Trees in

the Hardscape

Urban Tree Diversity

The Arb Show

ATF Meeting

July

Getting Trees Right

August

ISA International

Conference

European Tree

Climbing Champion-

ship

September

AA Conference

APF

Please submit your

calendar dates to the

Editor

MTOA Chairman, Moray Simpson.

The Chairman's Stump.

In deciding what to write about for this edition of the “Axe” I had originally

decided to look at the issues surrounding plant health and bio-security. This

is an extremely important and current topic; however this will have to wait for

another edition. So what changed my mind? Well at a recent Ancient Tree

Forum event, I was talking to a tree consultant, who told me about the

number of local authority tree officer posts lost recently in her area. This is

an issue not just relevant to tree officers, but for all that depend upon the

vital services that trees provide in urban areas. So I have decided to look what

we as tree officers can do to ensure our posts are not lost in this current

wave of cutbacks, thus ensuring that local authority tree services are not lost,

to the detriment of our urban tree populations.

So what can we do to save our jobs and thus ensure our urban forestry

programmes are on track to deliver the often mentioned benefits that we tree

officers know that trees provide? Well, in the past we have traditionally played

the “risk” card, using scare tactics to ensure our budgets are maintained. In

promoting local authority tree services this is a relatively negative tactic and

we have so much more in the armoury nowadays e.g. urban forest ecosystem

service benefits. Important as risk management of tree populations is, this is

just one part of a successful and holistic urban forestry programme.

I mentioned that we as tree officers know full well what benefits trees

provide, however are we getting this message across to the bean counters

that are currently cutting local authority services to meet the budgetary

An axe to grind, Pg.5

constraints imposed by the CONDEM government?

Some are and others aren’t. Well, as the cuts are

so wide ranging, we have to embed ourselves as

an essential service and urban forests as assets.

One of the best ways of doing this to have long

term adopted urban forestry/ tree strategies in

place. I say long term as we need to act smarter

and ensure that our urban forestry action plans

bring about real benefits in the long term. We

cannot strategically manage tree populations if

our targets and actions plans are for 5 – 10 years.

Think what 5 – 10 years is in tree time; it’s

nothing. When you’re planning to manage and

enhance tree populations, you can’t realistically

do this in a short time frame, you need long term

targets to make meaningful changes.

For those that don’t have an adopted tree strategy

in place, the main argument appears to be time,

or rather the lack off it. I have used this excuse

myself in the past. We’re so overworked

undertaking day to day duties that we don’t have

the time to write a strategy and ensure it’s

adopted by council. Well, we need to think again

and try and make time, as having an adopted tree

strategy may well save our posts from the chop.

Getting back to the local authorities who don’t

have a strategy, having a tree strategy was one of

the ten targets in “Trees in Towns II”. This report

stated that “local authorities develop and

implement a comprehensive tree strategy” (Britt &

Johnston, 2008). The authors of this report also

stated that those LA’s that have not got an

existing tree strategy and are not in the process

of developing one, need to make this an

immediate priority” (Britt & Johnston, 2008).

Trees in Towns II revealed that only 28% of

English authorities had an existing trees strategy

in place. You would hope that this figure is

higher now. In 2009, I surveyed all Welsh local

authorities on their arboricultural provisions and

this revealed that only 19% had a tree strategy in

place (Simpson, 2009). I’m aware that there hasn’t

been an improvement on this figure since then.

(Continued on page 6)

Table 1 Wales

(WLAAP 09

Survey)

England

(TIT II Sur-

vey)

Tree

Category

% of total Re-

sponses/ (No.

of Respons-

es)

All trees

(Council &

Privately

Owned).

66.67% (3) 42.72% (44)

Develop-

ment Site

Trees

0% (0) 13.59% (14)

TPO & Con-

servation

Area Trees

0% (0) 14.56% (15)

All Council

Owned

Trees

33.33 % (1) 11.65% (12) *

Council

Housing

Site Trees

33.33 % (1) 30.10% (31)

Highway

Trees

33.33 % (1) 26.21% (27)

Public Open

Space Trees

33.33 % (1) 22.33% (23)

Education

Site Trees

0% (0) 5.83% (6)

All Wood-

land

(Council &

Privately

Owned)

33.33 % (1) 13.59% (14)

Council

Owned

Woodland

0% (0) 29.13% (30)

An axe to grind, Pg.6

A tree strategy should be comprehensive,

encompassing all aspects of urban forestry.

In looking at the data provided by “Trees in

Towns II” and the Welsh Local Authority

Arboricultural Provisions 2009” survey in the

table shown at “table 1” overleaf, very few

tree strategies cover all aspects that an urban

forestry programme should.

The “Trees in Towns II” study also showed

that only 25.5% of English local authorities’

tree strategies contained specific targets for

tree planting and management (Britt &

Johnston, 2008). The authors said that “while

broad policy statements about the need to

plant more trees and improve the care and

protection of existing trees are to be

commended, these need to be supported by

action plans with specific targets that specify

how these objectives will be achieved. It

could be argued that any relevant strategy

document that does not include some targets

for tree planting and management is little

more than a mission statement” (Britt &

Johnston, 2008). So it’s not enough to have a

tree strategy, the strategy needs to be a

SMART document too.

So, to summarise, as tree officers’ we need to

work strategically to ensure that our posts

are not lost. We not only need to shout loudly

about the multiple benefits that trees and in

particular urban tree populations provide, we

need to ensure that our urban forestry

programmes are strategically embedded in

council plans.

References:

· Britt, C & Johnston, M (2008). Trees in

Towns II: A New Survey of Urban Trees in

England and their condition and management

(Research for Amenity Trees No. 9).

Department for Communities and Local

Government: London.

· Simpson, M (2009). A Survey of Welsh

Local Authority Arboricultural Provisions.

Unpublished.

(Continued from page 5)

An axe to grind, Pg.7

An axe to grind, Pg.8

Ancient trees are suffering

"unsustainable" losses because of

worries about failure, but a lack

of data on large trees being felled

is preventing campaigners from

making their case.

"More places are closing so they

don't have to intervene with their

trees so much," said Woodland

Trust ancient trees expert Jill

Butler.

"Incidents where there are

casualties and publicity put a lot

of pressure on other sites if they

can't close to the public. We'd like

the public to be more responsible

so these accidents don't happen

in the first place and not go into

sites where they're putting

themselves at risk.

"We feel there is a high rate of

loss and it isn't sustainable, and

our concerns are about rate of

loss because of natural events,

health and safety and lack of

knowledge."

She said an ancient tree such as

the Duke of Wellington cedar

(HW, 10 January), recently felled

by the National Trust at Kingston

Lacy in Dorset is irreplaceable

and planting young trees is like

destroying a Chippendale and

"replacing it with a reproduction".

Butler recommended Government

funding for top-quality tree

advice for landowners and a

national register of trees, similar

to listed buildings, to stop more

ancient tree loss.

Tree consultant Jeremy Barrell

said he is frustrated because "we

know it is happening, but cannot

substantiate it".

On the "rapidly depleting heritage

of old trees" he added that "risk

assessment has become so

complicated that arborists are so

confused they are taking the easy

option and felling rather than

taking the risk.

"I am seeing case after case

Kingston Lacy: ancient cedar felled at the National Trust property

NEWS

IN

BRIEF

An axe to grind, Pg.9

Looking to book for the ISA Milwau-

kee conference?

Www.isa-arbor.com

Click above for the

promo video.

where trees have just been felled

when there was an obvious and

easy management option." Barrell

said he advocates crown

reduction or fencing off.

Future heritage

Jeremy Barrell, managing

director, Barrell Tree Consultancy

"I am aware from general practice

that many large trees are being

removed and these are the ones

that will eventually become our

future heritage trees. What seems

to be happening is that the loss

of these intermediate trees is

diminishing the future stock of

heritage trees. The reality seems

to be that we do not know where

a lot of these trees are, which is

why we need a national register

like the listed buildings schedule,

which is why the Tree Council

Green Monuments initiative is so

important. Until we know what

we have got, we really will have

no idea of what we are losing."

The “Barcham Line”

Installed for £2.50 for those Tree Officers too lazy to supervise their tree planting!

An axe to grind, Pg.10

Forestry Commission finds more than

half of southern England’s woodlands are

likely to have been affected by the storm.

Around 10 million trees are estimated to

have died as a result of the St Jude storm

that swept across England last month,

according to Forestry Commission figures

released on Friday.

More than half (64%) of the 109,000

woodlands across southern England are

likely to have been affected by the storm

in some way but very few woodlands

should suffer long-term damage, the

results of a two-week survey show.

“I wouldn’t want anyone to be too

concerned by the large numbers of trees

affected by the storm,” said a commission

spokesman. “We need to remember that

this was a natural event with the effects

spread across many woodlands and they

have great capacity to recover.” Around

650 million trees remain across the area

the storm passed through.

Immediate ecological assessments

showed that woodland and ancient trees

survived much better than expected, with

tree loss nowhere near the scale of

previous powerful storms. The National

Trust and Woodland Trust, which between

them manage several thousand woods

across Britain, both reported little serious

damage.

The commission organised a two-week

survey of 165 woodlands from Cornwall to

Suffolk, searching for trees blown over or

snapped and looking at damage to their

crowns to assess overall woodland

damage.

The storm caused more damage between

Wiltshire and Kent with little or no damage

recorded at the south-west and north-east

extremes of the survey area.

By sampling clusters of woodland, the

commission found that 3.7% of trees

suffered damage to their crown (foliage

and branches), and 1.5% of area and trees

St Jude storm may have killed around 10 million trees

A BLUSTERY DAY!

An axe to grind, Pg.11

The winter's storms and rain

have caused unprecedented

damage to the New Forest's

trees, according to New

Forest National Park

Authority's senior tree officer

Bryan Wilson.

"This is extreme weather by

anybody's terms - a

succession of storms with

strong winds and continued

rainfall has been going on

since October with hardly

any respite," he said. "It is

worse than we had even in

1987 and 1990 storms."

Wilson's team, which covers

the National Park and wider

New Forest district, has had

to issue 160 notices for

urgent work to protected

trees in the four months

between October 2013 and

January this year, compared

to 30 notices in the same

period a year ago.

"The Tree Service telephone

has been ringing more or

less continuously over the

last few weeks with requests

from anxious landowners

seeking help and advice

about their or their

neighbours' trees," Wilson

added.

Lying mostly in Hampshire,

the New Forest has the

greatest concentration of

ancient and veteran trees in

western Europe. Around half

the National Park, which was

created in 2005, is

woodland.

Damage to New Forest trees "worse than

Great Storm of 1987"

Senior tree officer Bryan Wilson image:NFNPA

were affected by windthrow

and snap – where trees are

uprooted or broken by the

wind.

The damage was mostly

spread thinly throughout

woods and mostly affected

broadleaved stands – trees

like ash, beech, birch, elm,

holly, hornbeam, lime, oak

and poplar that have wide

leaves.

Most wind-damaged timber

will not be economic to

harvest and is likely be left

where it is, to turn into

valuable deadwood habitats

for wildlife. In the UK up to

one-fifth of woodland species

depend on dead or dying

wood for all or part of their

life cycle.

A BLUSTERY DAY!

An axe to grind, Pg.12

Hedging Your Bets!

Martin Sutton, the County

Arboriculturalist and Natural

Environment Manager for Shropshire

Council gave a very comprehensive

overview of the regs.

I will admit that when the MTOA

Board first discussed the idea of

a seminar on the Hedgerow Regulations

and there impact and management I was

somewhat sceptical as this was definitely a

departure from our normal “tree stuff” type

of seminar. I didn’t expect there to be

much of an interest from our members but

went with the opinion of the majority.

However, I am happy to say that I was

completely wrong (hardly the first time)

and we had a bumper crowd gathered at

the South Staffordshire District Council

Chambers, one of our regular and most

successful venues, for the MTOA’s

Christmas meeting which also doubles as

the AGM.

As you can see from the main picture the

room was pretty well full and the

atmosphere was the typical MTOA one,

plenty of good natured humour and plenty

of tall tales to be told, but this was not

really our usual crowd.

Next Meeting

See the inside back page for details of MTOA’s

next seminar “Trees in Crisis”, another not to

be missed value for money extravaganza on

the 14th May at Cannock Chase Museum.

Book your places straight away, download the

registration form here.

An axe to grind, Pg.13

Hedging Your Bets!

A review of the recent MTOA workshop

Andy Wigley, the Principal

Archaeologist and for Shropshire

Council

Emma Marrington,

Senior Officer for the

CPRE

For the first time in a long time we had

reached out beyond the usual suspects and

a large proportion of the crowd were

Landscape Officers, Ecologists,

Archaeologists, Conservationists and private

sector contractors, from all corners of the

country. A definite success!

There is no doubt that the quality of the

speakers helped draw the crowd, as you

would expect from an MTOA event but the

range of skills and depth of knowledge on

display was a pleasure to behold.

MTOA’s thanks would like to go especially

to Martin Sutton for doubling up on his

presentation after a train issue meant one of

the other speakers wen AWOL and a special

thank you must be extended to our own

Portia “Moksa” Howe for spending a great

deal of time pulling this all together.

MTOA has a full suite of dates over the next

few months with events in May, June

September and December planned already,

check out the diary page for more details

and book straight away.

AGM

The Annual General Meeting of the MTOA was

a fairly straight forward affair as it was a

“mid-term” meeting. All of the elected officers

were returned to post (details on our website)

Subsequently though we have ahd a resigna-

tion (see the last page of this magazine) and

so are inviting invitations to the membership

for a volunteer to fill this gap, please email

for details: enquiries@mtoa.co.uk

An axe to grind, Pg.14

T he UK has just experienced the wettest winter ever recorded with flooding

widespread across many parts of Southern England. Consequently millions of

trees will have faced prolonged periods of waterlogging stress. The

Environmental Agency are quick to point out that soils will still remain fully

saturated for up to two months even when the rain stops and the flood waters slowly

drain. Whilst all trees have evolved to tolerate some degree of waterlogging, the

extensive flooding recently experienced will undoubtedly negatively impact on their

current health and potentially leave them at greater risk of disease attack and by default

windthrow in the near-future.

THE PROBLEMS CAUSED BY WATERLOGGING

Whilst it may appear to be a relatively simple problem at first, waterlogging stress is

actually a series of significant events and processes, the severity of which increases with

flooding duration. Waterlogging begins when drainage is not sufficient to allow water to

pass freely from the root zone. This can happen for a number of reasons; compaction,

poor soil structure, layers of clay or volume of water entering the soil. Soils vary

naturally in their drainage by composition, clay, loam, sand etc. and geographic features

will also effect it.

An axe to grind, Pg.15

In urban environments, drainage is notoriously poor and trees

are often surrounded by impermeable surfaces such as tarmac

which funnel water to the exposed ground around their roots

and prevent wet soil beneath from drying. Under ideal

conditions trees should help to prevent stress on urban

drainage systems by reducing the volume of rain water

reaching the ground and helping return it to the atmosphere.

However this function requires that trees are kept healthy and

soil conditions play an important role in this.

Tree roots and the micro-organisms (mycorrhiza, bacteria,

arthropods) associated with the root system require oxygen,

provided by air filled pores. Waterlogging fills the pores in soil

with water preventing this. Typically oxygen moves into the soil

through these pores at a rate suitable for both the roots and

micro-organisms; however when they are filled with water

oxygen movement is reduced and eventually inhibited. If

(Continued on page 16)

An axe to grind, Pg.16

flooding is minimal i.e. the soil surface is still

exposed, only the upper soil layers receive

notable amounts of oxygen. If the water level is

above the soil surface oxygen levels are far

lower. In compacted soils, the pores are even

smaller, and as a consequence they fill up

quicker i.e. waterlogging is more severe.

As both the root system and associated micro-

organisms are oxygen dependent, any oxygen

present in the soil layers is quickly used up.

Normal function and growth of roots is

(Continued from page 15) interrupted. Once oxygen becomes

deficient “normal” aerobic soil micro

-organisms drop in numbers and

enter an inactive state until soil

conditions become more hospitable

again. Consequently micro-

organisms adapted to low oxygen

levels proliferate in their place e.g.

Paracoccus denitrificans,

specialized species of Clostridium,

Geobacter, Pseudomonas, and

Desulfobacter. Such micro-

organisms are associated with the

production of substances toxic to

the tree (ethylene, ammonium,

reduced iron and manganese,

sulphide), release of nitrogen from

soil and soil acidification.

Excess water also dilutes and moves

plant available nitrogen and other

nutrients away from the root

system. Tree roots can survive

without oxygen for a limited time

but not for prolonged periods.

Prolonged waterlogging influences

root metabolism resulting in the

build-up of toxic metabolites within

root tissue which accumulate and

damage the root cells. Root damage

during waterlogging is indicated by

blue-black discolouration and

peeling bark. Root tips and fine

roots, which are critical parts of the

root system for growth and nutrient

uptake, are especially at risk.

Waterlogging prevents normal root

function and therefore detrimentally

impacts on total tree biology. Due to

stomatal closure photosynthesis is

interrupted having two major

(Continued on page 18)

An axe to grind, Pg.17

An axe to grind, Pg.18

impacts. One, the tree is unable to

produce sufficient carbohydrates for

growth and so relies heavily on

carbohydrate reserves. These reserves

are mainly found in the root system and

so become at risk of depletion. The

longer flooding persists, the greater the

reserves exhausted. Two, inhibited

photosynthesis produces by-products

such as hydrogen peroxide and reactive

oxygen species which damage essential

chloroplasts and plant cells. Symptoms

are shown in the canopy of the tree as

leaf yellowing and senescence, reduced

fruit yield, wilting, shoot dieback and

decay.

Trees do have some adaptations to long-

term waterlogging such as producing

adventitious roots above the water line

and transporting air from above ground

through their tissues to the roots.

However tolerance to waterlogging and

the degree of use of such adaptations

varies markedly by species. Examples of

trees which often form adventitious roots

are: silver birch (Betula pendula),

common alder (Alnus glutinosa), giant

redwood (Sequoia sempervirens) and

willows (Salix spp.). Along with tree

species, plant age, as well as the

movement and properties of the flood

water are important factors in

waterlogging survival. Trees vary in

waterlogging tolerance between closely

related species and even within species.

(Continued from page 16)

An axe to grind, Pg.19

In general broad-leaved species are more

tolerant than coniferous species. The

season in which flooding occurs also has

an impact; dormant trees show greater

resistance to short-term flooding. The

speed at which the ground becomes

saturated is also important, as slower

waterlogging allows the tree to adapt to

some degree.

DISEASES

Damage to roots from waterlogging

stress leaves them vulnerable to decay

causing organisms. Excess soil water aids

and encourages the spread of infection of

major soil borne pathogens such as

Armillaria, Phytophthora, and Pythium.

Armillaria spread and growth is

enhanced by waterlogging. Phytophthora

and Pythium species are especially

adapted to attack hosts under

waterlogged conditions, having spores

with a flagella (tail) that allows them to

swim through saturated soil, attracted to

stress related substances released by

stressed roots. Retreating flood waters

can leave soil deposited around the root

collars of trees leaving them further

disposed to soil borne pathogens

MANAGEMENT PRACTICES

Application of treatments during flooding

poses logistical problems and

consequently has yet to be investigated

to any great extent. However, there are a

number of management practices that

can help trees recover from flooding

damage. Nitrogen fertilization has shown

promise in alleviating flood stress,

although it is not a complete remedy. It

resupplies nitrogen lost from soil during

flooding which is important for the tree

to produce proteins and enzymes

essential to growth, flood tolerance and

survival. Work at the Bartlett Tree

Research Lab has shown that it also helps

to direct resources to the roots which are

the key area affected by flood stress.

Improving soil structure, aeration and

drainage is a good strategy for a

preventative measure. This can be done

by air-spading and by adding porous

materials such as perlite or biochar which

has added plant health benefits. Biochar

amendment can also help retain

fertilizers in the soil. These structural

amendments keep the soil structure open

and can reverse compaction, allowing

water to drain from soils as quickly as

possible. Installing a drainage system is

also another option. General plant health

care practices following flooding are

important as waterlogging problems

persist once water has drained away.

Consequently, the legacy of the recent

floods in terms of tree health may extend

far beyond their retreat.

An axe to grind, Pg.20

A Surrey local authority

faces a stiff legal bill after

its attempt to prosecute a

developer and its

arboricultural contractors

for allegedly breaching a

tree preservation order

(TPO) was quashed by the

High Court.

Tandridge District Council

had tried to prosecute

Village Developments and

its contractors ATC

Arboriculturalists for

allegedly ring-barking four

oak trees on land

earmarked for development

in Oxted.

But following an appeal by

the two firms, the court

ruled that the developer did

not have sufficient notice

and were not obliged to

notify its contractor,

effectively blocking the

prosecution.

The TPO was first served

last March after nearby

residents found that the

trees, on the green belt

land, had been girdled.

Although the council had

served the TPO at the

addresses of the land's

registered owners, the

judge ruled it should have

been served at the same

time on Village

Developments, rather than

by recorded delivery post.

The council will now have to

pay the firms' costs of

around £75,000 along with

its own legal costs.

A council representative

said: "We are very

disappointed at the

outcome of the hearing. The

council will consider its

position further once the

written judgement is

issued."

Describing the case as "a

thoroughly nasty episode",

Village Developments

managing director Nigel

Greenhalgh said: "It seems

to have come about because

councillors put pressure on

officers to placate a group

of residents opposing our

development plans.

"Neither we not ATC were

aware of the TPO and

Tandridge did not demur

from that position."

Tree preservation order failings leave

council with £75,000-plus bill

An axe to grind, Pg.21

The Government has announced seven new

research projects valued at £7 million to

address pest and disease threats to

Britain's trees.

Launching the multi-disciplinary Tree

Health and Plant Biosecurity Initiative

(THAPBI), environment minister Lord de

Mauley said: "It is vital we invest in

research to better protect our precious

woodland from the future threat of pest

and disease."

Projects funded under the initiative are:

Population structure and natural selection

in the Chalara ash dieback fungus,

Hymenoscyphus pseudoalbidus –

£635,000, led by Professor James Brown,

the John Innes Centre.

Identifying genomic resources against

pests and pathogens in tree genera: a case

study in Fraxinus – £760,000, led by Dr

Richard Buggs, Queen Mary, University of

London.

Biological pest control of insect pests that

threaten tree health – £900,000, led by

Professor Tariq Butt, Swansea University

Promoting resilience of UK tree species to

novel pests and pathogens: ecological and

evolutionary solutions – £1.4m, led by Dr

Stephen Cavers, Centre for Ecology and

Hydrology.

Modelling economic impact and strategies

to increase resilience against tree disease

outbreaks – £900,000, led by Dr Adam

Kleczkowski, University of Stirling.

New approaches for the early detection of

tree health pests and pathogens – £1.9m,

led by Dr Rick Mumford, Food &

Environment Research Agency (Fera).

Understanding public risk concerns: an

investigation into the social perception,

interpretation and communication of tree

health risks – £615,000, led by Dr Clive

Potter, Imperial College London.

THAPBI is funded by the Biotechnology and

Biological Sciences Research Council

(BBSRC), Defra, the Economic and Social

Research Council, Forestry Commission,

Natural Environment Research Council and

the Scottish Government.

New £7m research package to tackle tree

pests and diseases

U rban canopy cover;

why does it matter?

In February 2007, I attended a four-day

Consulting Academy in Sacramento,

California, run by the American Society of

Consulting Arborists. We stayed in the

Downtown Hilton and from the balcony of the

ninth floor, there was a panoramic view out

over the city (photo 1). It is an image that

remains engrained in my mind because it

graphically demonstrated a dominant urban

character of buildings set within a treed

landscape. Most disturbing was that this was

not the way that many British towns and

cities looked, where character is dominated

by buildings, with a few trees fitted in here

and there, where there is space.

I wanted to understand why Sacramento was

so much greener than its British counterparts

and spent the next few months pondering

the reasons for such a stark difference. I was

booked to speak at the AA Conference in

Warwick six months later in September, and

my US experience significantly influenced

what I talked about. Something was clearly

wrong in Britain, I wanted to find out what it

was and, more importantly, work out what to

do about it. My presentation was titled

Trees; urban air-conditioning, and it was the

first airing of the idea that canopy cover in

British cities was declining.

I had always suspected that there was a

problem; for decades as a contractor, I had

been removing trees and it was obvious that

few were being replaced (photo 2). A gradual

denudation of urban canopy cover was

happening right in front of our eyes, but it

was so subtle that nobody had really realised

the cumulative impact it was having. Slowly,

but surely, a vital component for making

communities pleasant to live in was being

eroded away. Although subconsciously I

knew there was a problem, I had never really

thought about it in a strategic way until the

Sacramento experience exposed the grim

reality. The AA event was a turning point in

the canopy cover story because two

dedicated conferences soon followed run by

Neville Fay at TEP (www.treeworks.co.uk), and

today we have London imminently the

subject of the biggest i-Tree project in the

world. Canopy cover is now firmly on the

urban management agenda and that is a big

difference from back in 2007.

Since my trip to Sacramento, canopy cover

has dominated my thinking. I identified that

primary causes for the decline include; the

failure of arborists to understand and

promote the benefits of trees; the

complexity of tree risk management that has

resulted in arborists felling trees rather than

risk keeping them; the failure of local and

national government to understand the

importance of trees in creating and

maintaining sustainable communities; the

failure of local planning authorities (LPAs) to

prepare tree strategies; the failure of LPAs to

BS 8545: more of the same,

or something different? Jeremy Barrell, Barrell Tree Consultancy.

effectively use and enforce planning

conditions relating to existing and new trees;

a predisposition of highway authorities to

remove trees and not replace them; and,

most relevant to this story, a failure rate of

around 25% for new tree planting. None of

these reasons is the sole or dominant cause,

but nonetheless, I was convinced that all

were contributing to the cumulative and

relentless downwards trend of our urban

canopy cover.

Working towards the ultimate objective of

establishing and maintaining a fully stocked

and healthy urban canopy is the reason why

arboriculture exists and why arboriculturists

have a job, so canopy cover should be of

profound importance to us all.

What is different about BS 8545?

I am not a nursery specialist and I don’t know

much about tree planting, but I knew that

planting failures

was one small

part of the

bigger canopy cover picture, and I had

realised that seemingly small individual

improvements across the spectrum of

problems could make a big cumulative

difference. I sensed that increasing the

success rate of new planting was clearly an

important element towards reversing the loss

of canopy cover, but how could I contribute

to that cause? So, when Keith Sacre

contacted me around 2009 and asked if I

would help him with a new British Standard

on tree planting, I was interested because I

knew it would be important, but I also had

serious reservations. My experiences at

working with the British Standards Institution

(BSI) had all been bad; I perceived it as an

archaic and inward-looking organisation, with

a weak leadership failing to understand or

adapt to the demands of the modern

professional environment, and I had no

confidence in its ability to deliver a document

(Continued on page 24)

Photo 1: Sacramento in 2007 from the 9th

floor of the

Downtown Hilton, showing a landscape of buildings

among trees, as opposed to trees fitted in between

buildings.

of quality or value. However, Keith convinced

me otherwise, and I joined the group.

BS 8545 Trees from nursery to independence

in the landscape is different from the run-of-

the-mill material that BSI normally churns out

in a number of ways:

1. Panel members: Instead of the usual

focus on industry representatives, with all the

vested interest conflicts that brings, this

panel was assembled with an emphasis on

specialists of proven practical experience

across the range of disciplines that engage in

tree growing, planting and maintenance.

2. Lead author: The Trees and Design

Action Group (TDAG), in the way it prepared

and delivered its outstanding publication,

Trees in the Townscape, a Guide for Decision

Makers (www.tdag.org.uk/trees-in-the-

townscape.html0), has set a modern

benchmark in producing documents that are

relevant and easy to use for the target

audience. It did this through using a lead

author, who

compiled the

bulk of the content through extensive

consultation, with the assistance of leaders in

the multiple disciplines that the subject

embraced. The TDAG document

demonstrates the obvious benefits that arise

from this approach, namely consistency of

style, relevance of content and ease of use.

This BS panel adopted a similar approach,

with one lead author who pulled together all

the input from the panel of specialists.

3. Ease of accessing the content: A

priority throughout the preparation of this

Standard was that it would be easy to use for

the people who were growing, planning for,

planting and maintaining new trees.

However, we soon realised that there was so

much technical information and research that

to simply regurgitate all that material was not

feasible. At the same time, we were

conscious of the problems that BS 3998 had

encountered in getting to grips with the

same issue, and wanted to learn from that

experience. Indeed, BS 3998 was so lengthy

and difficult to use that it had prompted the

Tree Life Arboricultural Consultancy Ltd to

prepare an excellent concise version

(www.treelifeac.co.uk/bs3998), which is far

more useful on

a practical level

(Continued from page 23)

Photo 2: Site clearance in the 1980s; many of us suspected

that urban canopy cover was declining as trees were being

removed and not replaced.

than the original document. Towards this

end, BS 8545 has three layers of information;

the first and most obvious is that each

individual recommendation is listed as a

separate clause of one or two sentences in

the main body text of the document; the

second is a series of annexes behind these

recommendations to provide more prose-

orientated detailed explanation; and the

third is a list of the technical references and

links that readers can access if they need

even more detail.

4. Visual and conceptual content: It is

widely known and understood that diagrams,

flow charts and images are extremely

effective at engaging readers and imparting

important information quickly and clearly. In

that context, we carefully considered the

whole process of producing,

planting and maintaining

new trees, and created a

series of flowcharts to

conceptualise its key

components. These form the

basis of the body text and

each individual

recommendation flows from

that framework. This allows

users to easily understand the overview

quickly and identify the particular issue that

they require information on without reading

the whole document. Furthermore, although

the BSI framework does not allow

photographs (one of the multiple reasons

why the organisation seems archaic and out

of touch with the modern world), we were

able to introduce many diagrammatic

illustrations of important aspects within the

overall process.

BS 8545 is unique in many ways, and I pull

out just a few important points to emphasise

how it is relevant to emerging good practice:

1. Growing, supplying, planting and

maintaining new trees should be a

joined up process: One of the most

challenging difficulties with the existing

market for new trees is that their production

and sale by the producers is primarily

influenced by the immediate needs of the

consumers, i.e. a tree of a certain size at the

time of delivery, and hardly at all influenced

by the longer term needs, i.e. the tree

survives and thrives to maturity and beyond,

once it is planted. This Standard stresses the

importance of treating the growing, supply,

planting and maintenance of new trees as

one continuous process, which is only as

good as the weakest link in that process, i.e.

a failure of any part will compromise the

successful outcome of the whole. Achieving

the objective of new trees that can survive

and thrive to independence in the landscape

will require substantial changes to the

mindset of both suppliers and consumers.

Suppliers will need to think much more

carefully about species, provenance and

growing practice to increase tree survivability

after planting. Consumers will need to be

much more demanding in the quality of

plants they ask for and what they accept on

delivery. If successful, this

Standard will facilitate those

changes by empowering

consumers to clearly specify

what they want and motivate

suppliers to meet those

detailed demands.

2. Climate change:

Adapting to climate change will become an

increasingly important aspect of LPAs

managing their local environment and

increasing canopy cover is one of the most

effective way of buffering the direct impacts

on local communities. That means a focus

on bigger and longer-lived species that

provide more climate adaptation benefits for

longer. The importance of this as a planning

consideration is set out very early on in the

Standard at 5.4.3: “All planting projects

should be designed with the climate

adaptation benefits of trees in mind and

should specifically aim to contribute to the

national climate adaptation initiative”.

3. Finding out about and fitting in with

local initiatives: The nature of modern

tree planting schemes is that they are often

not very well linked and lack overall co-

ordination. This results in omissions,

misunderstandings and duplications of

(Continued on page 26)

How can tree officers

make a difference?

“Due Diligence”

effort, which are all counterproductive to the

objective of efficient canopy cover

management. This failing can be improved

by careful planning early on in the design of

a scheme by investigating what other local

initiatives are around and organising your

project within that wider framework. The

importance of finding out about other

initiatives in the design process is set out

very early on in the Standard at 5.6.2:

“Where appropriate, the design of new

planting projects should be informed by the

responses to community consultation and

local interest groups”.

4. Rooting through the bottom and

sides of pits: One practical focus, of the

many that this Standard embraces, relates to

tree rooting. It is widely, and often

mistakenly for the urban environment,

expected that trees will only root in the top

metre or so of the soil profile, and anything

deeper than this is not important. My

practical observations over the years

indicates that often the opposite is the case

in many urban conditions, i.e. that the upper

metre of the soil profile can be so hostile to

rooting that trees are forced to go deeper,

with species that can do so, such as plane

and lime, performing best in poor conditions.

This has direct implications for the design of

planting installations where there is a

presumption to use geotextiles to line the

sides and bottom of the pit. If these prevent

roots growing beyond the pit, and that

includes downwards as well as sideways,

then that may severely compromise the long

term survival of the tree through preventing

access to deeper and more distant soil

reserves. This is recognised and highlighted

in a number of places in the Standard,

namely in 10.2.4: “The use of geotextiles or

any other barrier to root growth, either at

the base of or along the sides of tree pits, can

limit root development into surrounding soils.

Unless there is a specific requirement to

inhibit root growth, such barriers should not

be used as a tree pit lining.” and in Annexe

F1.3: “It also seems likely that the use of

geotextiles to surround the cell installation

needs to be carefully assessed. Membranes

that are a barrier to root growth beyond the

planting pit prevent trees exploiting adjacent

native soil and can adversely affect long term

survival.” These clauses are intended to

assist users in making provision for longer

term tree survival by securing access to

extended rooting volumes.

How can tree officers make a

difference?

Although the burden of efficiently adapting

to climate change falls on us all, LPAs and

particularly tree officers, are well-placed to

have a significant impact, and quickly. Here

are some suggestions of positive actions that

tree officers can take to make a difference:

1. Get a copy of BS 8545: As a matter of

due diligence, all LPAs should have a copy of

nationally recognised guidance documents

and this Standard falls into that category. Of

course, there will be complaints about the

cost and funding cuts, but it is difficult to see

how any public body charged with

administering efficient development can

discharge its statutory duty without having

access to its own copy.

2. Talk to forward planning: All LPAs

have to prepare strategic plans and have

specific people in forward planning charged

with that function. Even if the bulk of the

LPA officers and members are not aware of

the requirements of the Climate Change Act

(2008) right now, they soon will be and the

specific requirement in that legislation for

LPAs to report on their progress in managing

the risk from climate change. As this Act

begins to bite in the next decade, LPAs will

be scrabbling to find ways to demonstrate

how they have managed the risks from

climate change, and climate adaptation

through the planting of new trees is likely to

be a very effective means of demonstrating

achievement. Even if it does not have a high

profile right now, planting new trees is soon

going to be very important and getting this

document cited in emerging plans will be a

(Continued from page 25)

very effective mechanism for delivering that

policy objective.

3. Write it into planning conditions:

Planning conditions are a

very effective mechanism

for administering

development, and

specifically referencing

this Standard in

conditions is likely to be

instrumental in

improving planting

success rates. However,

those conditions have to

be updated and tree

officers must be

proactive in initiating that process. All tree

officers should be talking to planners asking

for planning conditions to be updated to

specifically reference this Standard.

4. Use it in enforcement: This Standard

has been specifically written to empower

those who buy trees and oversee their

planting to be able to demand certain

standards, identify when those standards

have not been met and have the confidence

to challenge poor practice. When tree

officers discover poor quality trees or

planting, that are not in accordance with this

Standard, then its provisions give them the

means and backup to insist that minimum

standards are met.

5. Encourage its use: Tree officers are

often in a position to lead good practice by

referencing appropriate standards and

making it clear that they are expecting

compliance. Tell developers, planning

consultants, architects, landscape architects,

arboriculturists, and all the other

professionals involved in planning

applications, that they are expecting the

provisions of this Standard to be met in all

submissions. Then there can be no

complaints when inadequate planning

applications are delayed because of

insufficient information.

6. Seek out and promote instances of

effective use: One of the most effective

means of persuading doubting LPA officers

that a course of action is worth taking is to

show them cases in other LPAs where it has

been applied and the

benefits that have

followed. There will be

examples of LPAs that

get this right very

quickly and using them

as exemplars of how it

should be done will

often worry doubters

into action for fear of

being left behind.

7. Feedback: It would be impossible to take

on the task of producing such a complex

standard and get it right first time. This

Standard is new and is no exception, so

plenty of areas for improvement will emerge

as it is tested through everyday use and its

weaknesses are exposed. There is no doubt

that the panel have done the best they could

in the time available with the resources at

their disposal, but it is a work-in-progress,

and improvements will be needed. Everyday

users are the best-placed people to find

those weaknesses and feedback to BSI is the

mechanism to make sure problems are

considered at the next revision.

In summary, although there is still a long way

to go before tree planting success rates are

anywhere near acceptable, it is clear from the

above suggestions that individuals can make

a positive contribution to that overall

objective. Tree officers are in a very strong

position to drive change and, although each

action in isolation will be small and unlikely

to make much difference very quickly, the

cumulative impact of lots of people working

towards the same end has the potential to

deliver a much bigger result. As a group,

tree officers are extremely powerful and have

real potential to change planting success

rates. Knowing how to make a difference is a

good start, but doing something is even

better!

“Tree officers are in a very

strong position to drive

change . Knowing how to

make a difference is a

good start, but doing

something is even better!”

An axe to grind, Pg.28

London tree mapping

exercise “has just one

chance to get it right”

London tree officers have

been urged to get involved

in what is believed to be the

largest ever urban tree

mapping exercise this

summer.

Speaking to a London Tree

Officers Association (LTOA)

seminar on Friday 31

January, Forestry

Commission England urban

forestry adviser Jim Smith

explained that 66 teams,

each made up of a tree

expert and two assistants,

would be required to record

information on trees at

around 700 plot points

across the capital.

The information will then be

fed into the iTree Eco

application, which provides

policymakers with hard data

on the range of ecosystems

services that urban trees

provide.

“It’s been done in other UK

cities but they used paid

consultants,” he said. “Given

the scale and the budget we

have, this has to be

voluntary.”

Students on land-based

courses looking to gain field

data gathering experience

would make good

candidates to assist in the

work, he added.

Giving his support, LTOA

chair Jake Tibbetts said: “We

will only have one chance to

do this right.”

An axe to grind, Pg.29

Imported Dutch elm disease-resistant

elm trees could introduce the elm yellows

(EY) virus into Britain's already beleaguered

elm population, Forest Research has

warned, as industry views are sought on a

response to the threat.

Defra and the devolved authorities are

currently consulting with stakeholders to

develop a UK position on the virus, also

known as elm phloem necrosis, which is

spread by insects and by vegetative

propagation.

The consultation proposes a choice of two

courses of action:

A surveillance and awareness-raising

programme, to determine whether

additional EU or national legal

requirements would be justified, before the

start of the next planting season;

the same but with restrictions on

imports and movements of elm put in place

in the interim.

The plant health authorities already intend

to trace and destroy trees known to be

associated with infected batches.

Elm will also be added to the list of plant

genera whose importation from other EU

states must be notified to the authorities.

The disease is widespread in North America

and there have been a number of

outbreaks in Italy, France and Germany. It

was detected in a batch of Italian DED-

resistant 'Morfeo' elms being trialled in the

UK in 2012.

According to an assessment by Forest

Research, "The use of resistant elm

material from elm breeding programmes in

Europe has raised the possibility that EY

could be introduced into the UK via

planting stock potentially exposed to this

disease in the original place of production."

The UK native field elm (Ulmus minor) is

thought to be susceptible to EY, while the

wych elm (U. glabra) appears resistant.

Picture courtesy of the US Forest Service.

An axe to grind, Pg.30

Click on the picture for the full story or follow the link below.

http://myemail.constantcontact.com/For-Immediate-Release--Occupational-Tree-Care-Accidents-in-

2013.html?soid=1109594220206&aid=hnTOMvwLWfw

Fatality statistics from the US published

An axe to grind, Pg.31

Trees are Worth IT is an initiative that the

Midlands collective of the Trees and De-

sign Action Group are looking to get in-

volved with. Some of you will be aware of

this and Treezilla but for those of you

who aren't here's the basics.

Treezilla (visit the website

ww.treezilla.org - it's very informative)

calculates the ecosystem value of a tree

and converts it to a cash figure based on

two simple factors; its diameter and spe-

cies.

On 4th June 2014 we are hoping to 'price

tag' hundreds of trees across the region

for one day to raise public awareness of

what trees do for us. We hope to involve

local community groups, schools, tree

wardens, local authority officers, individ-

uals, businesses even but it's very simple

really.

1. In advance identify a tree which stands

out, is passed by lots of people or is

just fabulous.

2. Liaise with the owner

3. Just before the day on Treezilla type in

its co-ordinates, species and diameter

which will produce a monetary figure.

4. On the day write the monetary figure

on to a pre-printed label which we will

supply.

5. Tie the label to the tree , take photos

and post them on Treezilla.

6. The day after take the label off

If at any stage you can engage with a

school, the press, etc and make a bit of a

scene about it, excellent. But if you can’t

do it anyway.

Because Treezilla has the co-ordinates of

the tree it will plot it onto its national

map and you or anyone else can at any

time add photos, text etc on that tree.

Do you want to be a part of this? If so let

Julie Sadler

(julie.sadler@birmingham.gov.uk) know

and we will keep you updated.

We are looking for sponsors too! The

MTOA and Acorn Tree Surgeons have al-

ready pledged financial support which

will be recognised on the 'price

tag' . Sponsors might be local tree sur-

geons, businesses, etc. Let us know and

we will send details of what sponsorship

will involve and provide for.

Trees ARE Worth It!

Urban Tree Diversity Conference

I mages of a crushed car or flattened

house beneath a fallen tree tend to

accompany articles on tree risk. This

common image depicts an outcome of a

tree part failure that does not convey the

norm. The more typical scenario is depicted

in Image 1, a failure occurs and nothing

happens. Much of our reaction to tree risk is

driven by concerns regarding extreme

situations. Furthermore, our understanding

has been primarily informed through

litigation and tree biomechanics. The former

has more than likely skewed our perception

of liability, and the latter addresses only one

of the elements that determine tree risk.

Perhaps due to these factors, the

arboriculture profession tends to emphasize

the extreme consequences of a tree part

failure. Tree risk assessments and

management are complex topics and should

not be driven by the extremes. Those of us

within the profession who evaluate standing

trees for risk need to be fully informed on

this evolving subject.

A full discussion of this complex topic cannot

be presented in one brief article. The

purpose of this essay is to challenge

arborists, working both in private and public

sector, to further their understanding of tree

risk and to apply more rigorous standards to

their practice. One issue of consideration, at

least in North America, is the plethora of

ordinal tree risk rating systems that have

been developed over the last two decades.

The LANTRA Professional Tree Inspection

qualification and the recent transition of the

International Society of Arboriculture (ISA)

toward the Tree Risk Assessment

Qualification (TRAQ) provides an opportunity

to critically review our understanding of risk

and specifically the ordinal rating systems

that have been used to date. Closer study of

risk measurement concepts and ordinal

rating scales suggests that current ordinal

risk rating scales create an overreliance on

interpretations drawn from these scales and

newer forms of risk assessment may be more

appropriate within the context of our

profession.

The simplest definition of risk is the potential

of experiencing harm or loss. The

assignment of risk anticipates or attempts to

quantify the likelihood of an event occurring,

which is typically viewed as a negative event

when concerning trees. The risk

determination of an individual tree involves

the careful assessment and integration of

three components: (1) the identification of

the likelihood of a tree part to fail; (2) a

determination of the likelihood of that part

striking a target or impeding service if it

fails, and, (3) an evaluation of the

consequences if both likelihoods occur.

Our ability to reliably predict the likelihood of

a tree part failure combined with the

likelihood of the tree part striking a target

will only strengthen as we seek ways to

assess and measure these dimensions.

An Assessment of Ordinal Tree Risk Rating Systems

Currently,

the ability to identify tree risk is driven by

mostly qualitative methods. However, by

examining some of the weaknesses in

current evaluation methods and tools,

improvements can be made that may reduce

inherent bias in qualitative evaluations. The

United States Forest Service hazard rating

system, the ISA Pacific Northwest Chapter

TRACE program, and the ISA ordinal tree risk

rating scales are examples of instruments

currently in use to determine tree risk. They

assign a score to three factors: (i.e. size of

part, potential of that part to fail, and target)

and then combine the scores to derive a risk

rating.

Despite the prevalence of their use in the

field, the lack of empirical support for these

instruments is concerning. Moreover, the

interpretations drawn from these tools are

often times accepted independent of any

corroborating data points. Overreliance on

one data point to form interpretations

violates assumptions of measurement.

After a review of five ordinal rating scales,

four measurement issues were identified that

should be of concern to all within our

profession. These are: (1) the use of

category designations as mathematical

representations, (2) the multiple concerns

with the size of part classification, (3) the

limited interpretation of risk, and (4) the

range compression that occurs when the

composite risk rating is determined.

1. Misapplication of Category

Designations

Depending on the ordinal system used, one

to five points are assigned to each of the

(Continued on page 34)

Large Silver Maple Acer saccharinum failure without major consequences.

three factors mentioned earlier. The ISA

system (Clark and Matheny), shown above in

Table 1, assigns one to four points to each of

the three factors. The composite risk rating

is derived by adding the three factor scores

together to obtain a number from three to

twelve. Higher scores are assumed to

represent greater risk.

The tree risk rating scales that are used are

considered ordinal scales in which numbers

represent categories or rank. The numbers

do not represent quantities. In other words,

their assignment does not equal a

mathematical relationship. They represent a

group or range of data features. The practice

of adding the individual category scores

together to provide a composite risk rating

oversimplifies the phenomenon of risk and

suggests that simply adding categories

together yields a valid quantification of

comparative risk. It does not. Adding the

individual scores changes the use of the

number from a category representation to a

mathematical one, which is a measurement

error.

2. Multiple Concerns Regarding the Tree

Part Classification

Each ordinal rating scale requires the

assessor to assign a number to the size of

the part that is most likely to fail. As defined

by the ordinal rating systems, larger parts

are given higher scores. This practice has

inadvertently focused our attention on the

larger parts of trees as sources of failures.

This is contrary to our understanding of the

actual risk that may be present. Because of

the greater number of smaller branches that

exists in most trees, the potential for them to

fail and cause harm on any average day is

greater than the higher rated large parts.

The law of averages suggests that over the

course of an inspection interval there is a

greater chance of a significant small branch

failing and causing harm than a larger

branch. Cox (2009) identifies this as an

(Continued from page 33)

“Error in Comparative Rankings” which, in

this instance, means that higher risk ratings

are actually given to features that have less

likelihood of risk compared with others.

Another concern regarding the size of part

classification pertains to the categories’

exclusiveness and ranges. Exclusiveness is

required when features are categorized, that

is, data points cannot belong to more than

one category within an attribute. This is an

issue specific to the ISA rating system.

For example, a six-inch tree part resides

within two categories. This violates this

assumption of exclusiveness. The presence

of this methods violation allows assessor

bias in the rating process. Finally, there

appears to be no research to support the

development of the size part category ranges

for any of the ordinal rating systems

evaluated. This is particularly problematic

given the emphasis on higher scores in the

ratings and the potential for error that this

introduces.

3. Constricted Understanding of Risk

One of the complicating factors particular to

tree risk assessments is the large number of

variables that can contribute to risk

determination. Site, tree structure and

environmental factors are the three broad

categories that we must consider. However,

within each of these three main categories

are dozens of additional variables that

contribute to risk assessment outcomes.

Many of these variables place fluctuating

stresses on the tree over time—affecting

different parts of the tree at different times

and intensities. Multiple parts on a tree have

a potential to fail within an inspection period.

In addition to these numerous failure

potentials, target presence and placement

also fluctuates greatly over the inspection

period.

The ordinal rating systems have the

profession selecting the single part most

likely to fail when a target is present within a

defined inspection period. This methodology

constricts our understanding of risk by

negating the range of potential events that

could actually occur.

4. Range Compression

In all of the ordinal rating systems it is

possible that tree parts with obvious

differences in risk can be assigned the same

risk rating. Using the ISA system as an

example, a five-inch branch that has a severe

potential to fail in a constant use area has

the same rating as a thirty-two inch branch

with a low potential to fail in a constant use

area. Both scenarios have a rating of “9”, but

the smaller branch has the most immediate

risk associated with it. Cox (2009) defines

this error as an example of “range

compression” that is, an identical rating is

assigned to quantitatively very different risks.

An additional example of range compression

is that a significant small branch can never

have a composite risk rating greater than

nine (9) on the ISA’s twelve-point scale, ten

(10) on the TRACE twelve-point scale and

eight (8) on the USFS ten-point scale. There

are numerous tree-related fatality and injury

cases that involve a branch five or six inches

in diameter. All of the ordinal rating systems

(Continued on page 36)

fail to capture the risk associated with tree

parts that have the higher probability of

failing by placing greater weight on the

larger parts, which, in comparison, have a

lower frequency of failures.

Discussion

Within the arboricultural profession, the

understanding of the concepts of tree risk

are evolving and becoming more refined.

The LANTRA Professional Tree Assessment

Qualification, the recent release of the ISA’s

Tree Risk Assessment BMP

and the launch of the

Tree Risk Assessment

Qualification serve as

three examples where

this evolution is

providing an

opportunity for

arborists, consultants

and Municipal Tree Officers

to enhance their understanding of this

complex topic. Past instruments, though

flawed, have provided important initial

insights into tree risk assessments.

TRAQ, as an example, is not without its

flaws. Without a method of quantification,

“categorizations of relative severity cannot

necessarily be made objectively –

independent of subjective risk attitudes – for

uncertain consequences” (Cox, 2013).

However, TRAQ addresses some of the bias

inherent in the ordinal rating systems by:

(1) eliminating the size of part factor and

making it an element of determining

consequences,

(2) evaluating the likelihood of failure and

likelihood of striking a target as

independent processes of each other, and

(3) providing for the assessment of multiple

tree parts and targets.

In litigation, risk trees are most often viewed

in terms of absolutes—the tree part was

either a hazard or not. However, as we all

know, risk is about uncertainty and the

arborist profession falls prey to developing

poor policies or

misinterpreted

conclusions when

thinking about tree

risk in absolutes.

In many failure

litigation cases,

consultants are willing to

assign a post-failure risk

understanding to the pre-failure tree. In

many of these instances, unless very strong

visually overt defects are present, the expert

treads dangerously close to being an

advocate for the attorney rather than being

an impartial expert by assigning higher

ordinal ratings than would have been

assigned before the failure. As

professionals, we have the difficult task of

assigning risk ratings to a biological feature

with potentially dozens of variables at play.

It is rare to have a tree that can be

considered a hazard in absolute terms.

The purpose of this discussion is not to

diminish the expertise or contributions of the

(Continued from page 35)

TRAQ, as an example, is

not without its flaws,

but it addresses some of

the bias inherent in the

ordinal rating systems

instrument developers, rather the concepts

presented here are to afford balance in the

assessment process. Instruments will always

generate data, but it is the role of the

assessor to make interpretations from

measurements. An overreliance on the

numbers generated from the use of these

scales may skew the understandings of risk.

Given the qualitative nature of our rating

systems, arborists must base their

interpretations on findings from multiple

instruments. In this way, the professions

individual and collective understanding of

risk will mature.

Citations:

Albers, J. 2002. Urban Tree Risk

Management: A Community Guide to

Program Design and Implementation. USDA

Forest Service

Cox, Louis A, 2009. Risk Analysis of Complex

and Uncertain Systems, International Series in

Operations Research and Management

Systems, Springer Books, London, United

Kingdom.

Dunster, Julian, 2009. Tree Risk Assessment

in Urban Areas and the Urban/Rural Interface:

Course Manual. Pacific Northwest Chapter,

International Society of Arboriculture,

Silverton, Oregon.

Matheny, N. and Clark, J, 1994, A

Photographic Guide to the Evaluation of

Hazard Trees in Urban Areas. Second Edition.

International Society of Arboriculture, Savoy,

Illinois.

Tabachnick, B.G. & Fidele, L.S. (2007). Using

Multivariate Statistics, 5th

ed. Pearson

Education, Inc., Boston, Massachusetts.

An axe to grind, Pg.38

Well it’s that time again and

my, what a time it’s been.

This edition’s fungal curio

worth watching out for is

juniper-hawthorn rust,

caused by the delightfully

named Gymnosporangium

clavariiforme. The fruiting

bodies can be really quite

beautiful when seen in great

numbers, earning them the

formidable name of ‘tongues

of fire’. However, this

enigmatic Bella Donna of

fungi is parasitic on both

juniper and hawthorn and

can have serious

consequences for both

species.

All Gymnosporangium

species are heteroecious,

which means they need two

different hosts to complete

their life cycle. The primary

host is almost exclusively a

species of juniper, while the

secondary hosts are all

members of the Rosaceae

family, including quince,

apple, rowan, pear and

amelanchier. G.

clavariiforme is exclusive to

hawthorn, meaning that if

these fruiting bodies are

seen on a juniper, it

necessarily follows that

somewhere nearby is a

hawthorn suffering from

rust.

The intriguing life cycle of G.

clavariiforme begins

therefore with our wild

juniper. Spores infect juniper

in mid-summer, causing

branches to enlarge. From

these during wet weather in

the following spring, orange

fungal growths known

fantastically as ‘telial horns’

emerge, which produce vast

quantities of spores,

allowing infections to spread

for several miles through the

air. These growths will dry

out, but are able to re-grow

if more wet weather occurs,

extending the sporolation

period.

Spores will infect hawthorn

in the early blossom stage,

entering the leaf and fruit

tissues. Yellow spots will

appear on leaves in around 2

-3 weeks, which develop into

round, red, swollen galls.

Later, rust will be seen on

the fruit, which will often

become deformed and

useless. Spores are then

released from the underside

of leaves in summer, which

then go on to re-infect

nearby junipers, starting the

cycle all over again. Both

species can suffer as a

result, leading to die-back of

branches and death in

extreme cases.

Fig. 1: Major die-back on juniper

An axe to grind, Pg.39

Control of all

Gymnosporangium

species is difficult.

Fungicides can be

used on fruit trees,

but once spots are

seen on leaves it is

already too late to

treat infections. As

both species are

needed for the

fungus to

reproduce, one

obvious control

method would be to

remove as many nearby junipers as possible to break the infection cycle, depending of

course upon which trees you value most! While this may be possible in orchard

situations, it might not be a

popular solution with the old lady

next door. However, there are

resistant trees available, so all is

not lost. Either way if you see

these galls grab your camera,

they’re an excellent photo

opportunity!

Chris Parker.

For more background reading I

recommend the following website.

http://www.naturespot.org.uk/

species/tongues-fire

Cheers!

Fig. 2: Fruiting bodies as seen on hawthorn

Fig. 3: ‘Telial horns’, or ‘tongues of fire!’

An axe to grind, Pg.40

A fresh outbreak of the deadly

Dutch Elm Disease is threatening

to wipe out the city's national col-

lection of the endangered trees.

Five elms riddled with the dis-

ease are set to be felled while

further “sporadic outbreaks”

across Brighton and Hove contin-

ue to be monitored.

The disease, which is spread by

the elm bark beetle, wiped out

some 25 million elms across the

UK in the 20th century.

But thanks to the protection of-

fered by the South Downs and

English Channel and the skill of

local arboriculturists, many of

the city's trees survived.

Brighton and Hove is now home

to the only substantial collection

of the species in the country and

as a result was awarded national

collection status in the 1990s.

However, the remaining 17,000

elms are now under threat fol-

lowing the fresh outbreak.

Four diseased trees in the Old

Steine Gardens are set to be de-

stroyed next week.

A further diseased elm has also

already been felled on

the University of Sussex's Falmer

Campus.

Brighton and Hove City Coun-

cil environment committee chair-

man, Pete West, described the

outbreak as “extremely worry-

ing”.

He said: “It is more than likely

down to imported fuel logs or an

elm tree that is already infected

by elm bark beetles which carry

the fungus.”

“We implore local residents and

businesses to contact our parks

department immediately if they

suspect they have elm timber as

logs or a suspect elm tree on

their property.

“This is urgent.”

The 25 metre-high elm which

was felled on the Falmer Campus

is thought to have been around

150-years-old.

Andy Jupp, the university's assis-

tant director of estates and facili-

ties management, said: “It's a re-

al shame but prompt action to

destroy infected trees is the only

way to limit the spread of this

devastating fungal disease.

“The fact that many excellent

specimens survive on campus -

including some of the largest

English elms remaining in the UK

- is largely due to the assiduous

efforts of estates staff over the

last 40 years to remove any in-

fected trees as soon as they show

symptoms of the disease.

“In the long term our actions this

week will help to protect the oth-

er elms on campus.”

For more details visit brighton-

hove.gov.uk/elmdisease.

An axe to grind, Pg.41

An elm in the middle of the Bulgarian city

of Sliven which is thought to be over a

thousand years old has has won an online

poll to find the European Tree of the Year.

The contest, organised for the fourth year

by the Czech Environmental Partnership

(Nadace Partnerství, NAP), pitted trees from

ten European countries together, with the

Bulgarian entry taking nearly half of the

nearly 160,000 votes cast across the conti-

nent.

Known simply as The Old Elm (Stariyat Bry-

ast), the field elm (Ulmus minor) serves as

a symbol of Sliven in eastern Bulgaria, and

features on its coat of arms. It is frequently

evaluated by city authorities and its base

reinforced.

Scotland's entry, Niel Gow's Oak in Perth-

shire, came seventh, Ireland's Birr Castle

Grey Poplar in Co Offaly came eighth, and

Wales' Oak at the Gate of the Dead, Wrex-

ham, was ninth.

Each of the ten had already won a national

heritage tree contest.

Explaining the contest, its website said:

"We are not searching for the oldest, the

tallest, the biggest, the most beautiful or

the rarest of trees. We are searching for the

most lovable tree, a tree with a story that

can bring the community together."

The award ceremony took place at the Eu-

ropean Parliament building in Brussels on

Wednesday 19 March.

Thousand-year-old city tree

“European Tree of the Year”

An axe to grind, Pg.42

C oming from a forestry

background, Urban Forestry is a

term I use a lot and one which

many of us will be familiar with. But what

do we actually mean when we talk about

the urban forest?

Understanding the definitions involved is

important because people have different

interpretations of what constitutes the

urban forest. Do we mean the street

trees? Or a specific woodland in an urban

area? Do we include shrubs, lawns or

parks?

There also appears to be some difficulty

in defining what is ‘urban’. As yet, there

is no international agreement on the

defining characteristics of the urban

habitat (cited in the recent UK National

Ecosystem Assessment). The Office of

National Statistics in the UK simply

classifies ‘urban’ as contiguous areas of

settlement with a population of 10,000

people.

We also need to be mindful that for many

people even the very term ‘Urban Forest’

seems oxymoronic, the use of two

apparently contradictory terms put

together. They ask, “How can an area be

simultaneously urban, and forest?”. Well,

in my view it can, and this is why...

Broadly speaking, there are two main

interpretations of what constitutes an

‘urban forest’. The first looks at the sum

of all urban trees; including those

situated in parks or in streets, on both

private and public land, and considers

orchards, hedges and other green spaces

across the urban area under

consideration to collectively make up an

‘urban forest’ (See Grey and Denke’s

Urban Forestry for example). In

In this, the first part of a two part article, Kenton Rogers takes a

look at what actually makes up the “Urban Forest” . Above is a

picture of Torbay, the site of the UK’s first full iTree survey

undertaken by Kenton and his company, Treeconomics.

An axe to grind, Pg.43

Konijnendiijk’s ‘Defining Urban Forestry’

paper this is called the ‘broad’ definition.

The second refers to urban forest as

individual units within an urban area and

in Evans’s Forest Handbook is described

thus, ‘Urban forests can be defined by

their placement in or near urban areas’.

This second definition refers to distinct

areas of woodland within an urban area

as urban forest, the ‘narrow’ definition.

Although not technically incorrect, in my

view this is a less helpful concept as it

separates out the ‘urban’ from the

‘forest’ and oversimplifies the spatial

relationship between the two, implying

that they can indeed by separated.

I much prefer the definition given by

Sands (in Forestry in a Global Context

2005), who takes ‘the trees found in

streets, municipal parks, gardens and

reserves, golf courses, cemeteries,

around streams, on private property, on

catchments, in greenbelts and indeed

almost everywhere‘ to make up the urban

forest. He goes on to state ‘The urban

forest is the ecosystem containing all of

the trees, plants and associated animals

in the urban environment, both in and

around the city’.

This definition is much more holistic and

looks at the urban forest in the same way

that a traditional forest might be

considered. It also introduces it as an

ecosystem too. Again, ecosystems are an

important part of the urban fabric, yet

they are often (incorrectly) viewed by the

general populace to be something

separate from ‘urban’. Something

perhaps one might pop into the car and

drive off to and visit out of town.

Deneke (in Grey and Deneke’s Urban

Forestry) goes so far as to say that ‘cities

are forests’ and by United Nations

definition - Land with tree crown cover of

more than 10 percent and area of more

than 0.5 hectares - most cities and urban

areas could indeed be classed as forests.

It has been argued that perhaps we

should stop thinking about the trees in

our towns and actually consider towns in

our forests instead. This is by no means a

new ideal, and visitors to 17th century

Amsterdam often remarked that they

could not tell if they were in a city or a

forest.

John Evelyn visited in 1641 and was very

impressed by the quarter known as

Keisers-Graft ‘which appears to be a Citty

in a Wood, through the goodly ranges of

stately and umbrageous Lime trees,

exactly planted before each mans doore’ .

Considering the broad definition of urban

forest and starting to think about the

towns in our forests, brings trees and

other components of the natural

environment to the fore. This is

important because its the urban forest

which makes our towns and cities livable

places. Its is especially the case when we

consider future changes in our climate,

which will be felt first and foremost in or

urban areas.

The benefits provided by the urban forest

are many and are well documented. Trees

filter pollutants, reduce the urban heat

island effect, provide aesthetic interest,

improve health and can even reduce

crime or encourage greater consumer

spending. These benefits are also

provided simultaneously and at relatively

low cost. The benefits are even more

pronounced in urban areas, because the

urban environment is where most people

live.

The number of people living in Urban

areas of the UK for instance is currently

estimated at around 80%, or 44 million

people (ONS 2005). Globally, over 50% of

the worlds population now live in cities

and this is expected to rise to 60% by

2030 going by United Nations estimates.

Yet trees in urban areas are often under

the greatest pressure (from increased

summer temperatures and pollution

(Continued on page 44)

An axe to grind, Pg.44

levels to compacted soils, intensive

development, salt contamination and

vandalism to name a few).

Consequently, in the UK at least, tree

numbers have been steadily declining

(Britt and

Johnston

2008) in

our urban

areas. However, with increasing

urbanisation there is an ever increasing

need to incorporate the role of the urban

forest into long term planning and climate

adaptation strategies, in order to improve

the environmental quality of where we live

and work.

Yet, we know very little about our urban

forests, how they are growing, what they

are composed of, the tree species,

biodiversity and age classes for example.

Generally, the majority of Local

Authorities (LA’s) in the UK have scant

information (Britt and Johnston 2008) of

the tree stock and this is normally only on

public realm trees.

Few doubt that individual tree

management is important in our towns

and cities but if we completely neglect the

wider ‘urban forest’ view we inevitably

miss the bigger picture. Its much

overused but the old saying ‘seeing the

wood for the trees’ is a both a wise and

timely one for urban foresters, tree

mangers,

planners

and other

allied

professions.

Next time I will be looking at one of the

simplest ways to start investigating the

urban forest, analysing canopy cover.

Kenton Rogers is a Chartered Forester

and Fellow of the Royal Geographical

Society. His current projects include

Treeconomics, a social enterprise that

engages with public bodies, research

organisations communities and

commercial businesses to highlight the

value of trees.

Email kenton@treeconomics.co.uk

(Continued from page 43)

The Urban Forest; Reigate pictured from the North Downs.

An axe to grind, Pg.45

Tree Strategy

Or

Street Tragedy? All work courtesy of the National Grid

Then

Now

An axe to grind, Pg.46

U rban vegetation is often

subjected to extreme

environmental conditions related

not only to higher atmospheric pollution

levels caused by traffic and other

anthropogenic emissions, but also to limiting

water availability and higher temperatures,

typical of the city's microclimate. Due to the

negative future prospects for the urban

environment caused by climate change

(higher CO2

concentration, higher

temperature and changes in rainfall pattern),

there is a need to monitor and manage pro-

actively urban greening and peri-urban

forests. Urban trees provide a unique

opportunity to address both climate change

mitigation and adaptation but we clearly

need more basic data about urban trees, and

urban green in general. Research projects

have shown that, in the short time, the

exposition to high CO2

levels, can reduce the

stomatal conductance and might increase

photosynthesis and

growth up to 20-

50%, according to

the species, plant

age and water and

nutrients availability.

Existing data needed

to understand the

adaptation of

photosynthetic

apparatus to CO2

increase are still

lacking, above all

when it acts in

interactions with

other climate

parameters, like

temperature and

water availability. For

this reason,

understanding how

the increase of

temperature will

modulate plant responses to increased

atmospheric CO2

has been described as a

priority for the research on climate change.

Trees will be affected by this rapid climate

change because of their long life span and

the slow rate of genetic adaption. With a

proactive management strategy (i.e. acting in

advance of a future situation), urban forests

and trees have strong potentials to mitigate

the impact of global warming such as

extreme heat waves.

What is currently known

According to the Intergovernmental Panel

on Climate Change (IPCC) Fifth Assessment

Report (2013) the surface air temperature

will increase 1-2.5°C by the end of this

century. Drought spells are predicted to be

most significant not only in the

Mediterranean-like climates and this will

strongly influence survival and growth of

newly planted trees and will probably affect

the development of diseases and tree pest

What we should expect from research results?

An axe to grind, Pg.47

resistance. Not only are the short-term

effects important, but also the long-term

impact on growth has to be considered in

selecting planting material. Selecting trees

that use water efficiently without the need

for frequent watering or irrigation is one

way to make your landscape more tolerant

to drought and is the best long-term

solution to a healthier, low-maintenance

landscape. In this scenario possible

adaptation measures include changes to

establishment practice and tree

management, better matching of species to

site, both under current and future

climates, and the planting of non-native

species and provenances in anticipation of

climate change (Ghannoun and Way, 2011).

However, local provenances may not be able

to adapt to a changing climate, particularly

given the rate of change predicted. Sourcing

planting stock from regions with a current

climate similar to that predicted for the

future may provide one option, although

care must be taken to ensure that suitable

provenances are selected which are not at

risk from, for example, spring frost damage

as a result of early flushing (McCarthy et al.,

2010).

The issue is also

complex: environmental

factors can significantly

influence the chemistry

of the atmosphere. VOCs

emitted by plants mix in

the atmosphere with

anthropogenic gaseous

compounds, and

depending on the

compositions of these compounds positive or

negative effects on tropospheric O3

and

particulate concentrations in the atmosphere

may occur, through complex photochemical

reactions not yet fully studied. In summary,

the functional roles of secondary metabolites

in plant-environment interactions is to be re-

visited taking into great account their

capacity to avoid the generation of, and then

reduce various Reactive Oxygen Species

(ROS) by complementing the functions of

primary antioxidant defenses. Clear guidance

is needed for local authorities and other

practitioners on how best to manage public

urban green spaces in order to respond to

climate change. Therefore, as a proactive

measure, urban foresters should consider

using species suitable for future climates in

current urban greening projects.

What research should aim to

Research should aim to develop basic

knowledge which could be useful to deal with

practical issues in the crucial field of the role

(s) of trees in improving environmental

conditions in our cities, with special regard

to the foreseen environmental scenarios due

to climatic change. We know that in the

future CO2

and O3

air concentrations will rise,

temperatures will be higher and water

availability will change. So doing, criteria and

strategies for the selection of ornamental

woody species to display in the future cities

must be clearly defined. The intimate

mechanisms of plant response to

environmental oxidative stress should be

elucidated, with special

regard to secondary

metabolism and the

transduction of the

stress dependent signal.

The analysis of plant

physiological

performances and stress

indicators in the urban

environment, both in the

current conditions and under simulated

future scenarios will allow to evaluate the

contribution of urban forests to improve the

quality of life, by the assessment of the

ecosystem service of air quality improvement

provided by urban green.

Micrometeorological investigations with

(Continued on page 48)

“urban foresters should consider

using species suitable for future

climates in current urban

greening projects”

An axe to grind, Pg.48

https://www.youtube.com/watch?feature=player_detailpage&v=d260CmZoxj8

highly innovative measurement techniques

(eddy covariance) will clarify plant/

atmosphere relationship as well as energy

fluxes in urban and suburban reference

selected sites. In addition, they will carve

previously unexplored aspects of the

interactions between urban vegetation and

atmosphere, i.e. flux determination of VOCs

emitted by urban vegetation, their oxidation

products, and their fate in the atmosphere

which impacts the concentration of

tropospheric ozone. This will allow using the

model for urban planning purposes,

therefore it could be widely accessed by the

scientific community and beyond. Research

results may therefore be useful to

stakeholders, such as municipal managers

and city planners, to establish the best

management strategies to improve the

pollutants sink capacity and climate change

mitigation of urban vegetation in future

climatic conditions.

Francesco Ferrini and Alessio Fini

Department of Agrifood

Production and Environmental

Sciences – University of

Florence (Italy)

Citations

Ghannoun, O. e D.A. Way. 2011. On the role

of ecological adaptation and geographic

distribution in the response of trees to

climate change. Tree Physiology,

31:1273-1276.

IPCC, 2013. Climate Change 2013. The

Physical Science Basis. Working Group I

Contribution to the Fifth Assessment Report

of the Intergovernmental Panel on Climate

Change.

McCarthy, M.P., M.J. Best, R.A. Betts. 2010.

Climate change in cities due to global

warming and urban effects. Geophysical

Research Letters, 37.

doi:10.1029/2010GL042845

(Continued from page 47)

An axe to grind, Pg.49

Case 1

Felling of an Ash tree protected by a TPO to

the rear of a residential property. No

application was granted or sub-mitted for the

works, and following investigation the

management company who looked after the

property; the company who accepted the

quote to carry out the works; and the tree

surgeon who carried out the works, were all

interviewed under caution and the offence

borne out, and admitted by all.

At this stage the Council had a case to take

to court, but before that was agreed the

management company offered to replace the

tree, and also provide funding to plant trees

throughout the District. This funding was

informally agreed following assessing the

costs of taking the case to Court, and an

estimated fine imposed by the Court having

regard to the facts of the case.

In this instance, the Council's budget for tree

planting was given £3000 by the offenders

for tree planting throughout the District. As a

result the case was not brought to court.

Now the offenders suggested this

undertaking to the Council, and although no

formal undertaking was agreed (since having

taken legal advice undertakings are not

enforceable) the funding was provided

without delay from the offenders.

Case of the Month, extracted from the RTPI Networks Newsletter; NAPE News - April 2014 .

Our grateful thanks to Portia Howe and Gareth Hare of Lichfield District Council for bringing

this item to our attention. The below article is reproduced unaltered for your information and

the enforcement officers details have been left in just in case you wish to make a comment on

this directly to him.

Case 2

Felling of a Silver Birch tree to the front of a

site being redeveloped for housing. No

application was submitted or agreed for the

works, and following investigation the de-

veloper was interviewed under caution. In

this instance the defence that the tree was

dangerous was argued, although a statement

taken by a witness suggested other-wise. The

fact that a brick wall had been erected in the

location of the felled tree all seen by the

witness to take place within an hour of the

tree being felled, indicated that the reason

for felling the tree did not appear as what the

developer suggested. Following this interview

further works to other trees on the site had

been discovered.

As above, the developer agreed to fund the

Council for planting trees not only within the

District to avoid going to Court, but in the

site also since it was being redeveloped for

housing. In this instance, the developer

provided £11000.

(Continued on page 50)

Summary

Now both cases don't take away the

seriousness of felling a protected tree

without permission. However, if the harm

mitigated by the felling can be offset by

replacement planting, and funding for trees

to be planted throughout the District to

reinforce the Council's commitment to trees,

I thought this course of action is something

to be considered, of course on a case to case

basis. One benefit of this is the costs

involved for all sides involved in bringing the

case to court such as Officer time, Court

time, and removes the unknown result that

will be the Court's decision.

Both cases involved negotiations with the

offenders, me as the Council's Enforcement

Officer, and the Council's Arboricultural

Manager. I think the prospect of criminal

proceedings being brought was enough to

result in the funding being provided. Also, in

the case of the developer who had not been

in this situation before, it made them aware

of the seriousness of what they had done,

and I think in future proper procedures ie:

applying for planning permission first, will be

followed.

John Macauley,

Planning Enforcement Officer,

Shepway District Council

(Continued from page 49)

Commentary

Stuck for some tree planting funds, folks? It

seems that our planning colleagues have

come up with a novel idea to supplement the

council coffers and bag a bunch of new trees

into the bargain. Unfortunately I'm left

feeling uneasy about this way to 'avoid the

courts'.

Firstly I'm not sure there are provisions in the

act and regulations that provide for the

Council accepting money in order to waive a

prosecution in relation to a TPO

infringement. Whilst we should all take

mitigating and aggravating circumstances

into account, and whether the prosecution

would be in the public good, sadly weighing

'the public good' of a successful prosecution

against a different 'public good' of more

funds for tree planting or the cost of officer

time doesn't sit well with me. I think there is

a strong possibility of the council being

exposed to criticism in taking money -

particularly from a developer - as a way to

avoid the courts. Were I a householder being

threatened with court action for a TPO

offence I would certainly be pointing a finger

and saying 'they paid cash to be let off'.

Negotiating a cash sum or tree planting in

kind also leads to the question - how much

for this offence? ... in comparison to this

one ...? It is not our place as the local

authority to decide how much an offence is

'worth'. From my own experience it can be

galling that the fine goes into the nation's

pocket rather than coming back to our own

authority, but that is how it is. And yes, its

possible that you would get more out of

someone who had committed an offence

through negotiation than you would see in a

fine. Racking up the cash cost certainly

makes us feel good - justice feels as though

its been done - but in fact I don't think

justice or the TPO legislation is well served

by this type of settlement.

Firstly, the point of magistrates court is that

those deciding on the matter are

independent. This is actually fairer on the

person who has committed the offence - as

the magistrates may actually consider that

the council does not have a strong case.

Ethically, to me, this is important.

Administering the TPO regulations should be

transparent and even-handed. People have the

right to have an appeal independently

assessed. People should also have an offence

considered independently if the situation is so

serious it merits prosecution. And if it merits

a 'settlement' I would imagine it is serious too.

Settling this way could lead to the tree

surgeon, developer or individual feeling 'they

got away with it' even if they had to pay out a

reasonable sum. Are they less likely to do it

again? I don't know. But I know the experience

of a PACE interview, getting a solicitor, going

to court and standing before the

magistrates can have a hard hitting effect and

supports the TPO regulations. A successful

prosecution can be announced in the press,

repeated to local contractors as a warning and

tells developers that your authority does have

teeth. Going forward with a prosecution can

make a company look carefully at its own

chain of command and responsibility. I'm

aware of a site manager who was swiftly sent

on his way after taking down protective

fencing and directing all the plant between

TPO trees because it was 'quicker' once

the regional director was invited to a PACE

interview.

And finally I have to ask - why 'avoid the

courts'? Its not to my benefit to avoid the

court. It can be a struggle to get council

solicitors to take the risk of a prosecution -

but that's not a reason to try and avoid it if

after consideration the prosecution is in the

public interest. The only person who benefits

from avoiding court is the offender -

obviously, they must think so if they are

prepared to pay more to the council than they

would likely pay in a fine. I wasn't aware we

were having a season of magnanimity in the

arb world!

Does anyone else have thoughts on this?

Have you tried it - did it work? Email your

view; enquiries@mtoa.co.uk

Inspector rejects appeal to fell

300-year-old oak implicated in

garage subsidence

An appeal seeking to fell a mature English oak

tree in a north London garden has been

rejected by the Planning Inspectorate.

The tree stands by the garage in a communal

garden near a conservation area in the London

Borough of Enfield and is subject to a tree

preservation order.

The inspector noted that it was in reasonable

health, visible from a public highway, that it

had high amenity and biodiversity value,

and that a local residents' association had

launched a petition to save it.

It was also judged that, though tree was likely

to have caused a material effect on the

property, the level of cracking was "not

significant".

While the appellant may pursue a claim against

the council to reinstate or underpin the

garage, this was judged to be insufficient

reason to permit the loss of the tree - the

felling of which could anyway cause additional

problems through "heave", the inspector

noted.

The original application to fell was rejected by

the council last year. The appellant was

Nicholas Meyer of arboricultural consultancy

and mitigation service OCA UK, who also made

the original application in April 2013, rejected

by the borough

Image: FLDRA

An axe to grind, Pg.52

On 1st

April

(no joke) 15 riders decked-out in the usual

bright canary-yellow Ride for Research t-

shirts set off from Birmingham University.

The ride was ahead of the ICF’s 2014 Trees,

People and the Built Environment II (TPBE)

conference billed as the largest ever

gathering of environment professionals in

the UK.

After an unfortunate stalled start caused by

two exploding inner-tubes with Sharon

Hosegood’s bike, we set off at a brisk pace,

up hills and down Birmingham’s back alleys

and green corridors that extend throughout

the city. With blackthorn trees in flower and

bright sunshine, the day’s news item about

Saharan Desert dust and high European

industrial pollution levels seemed a long way

off. Yet at the back of our minds, and

thinking about the TPBE conference, we

realised how important it is to ‘green’ our

high tech industrial world.

Reaching the first school – Woodgate Primary

– early we waited around the corner in

anticipation of a whole school turn-out and

an enthusiastic welcome. We were not to be

disappointed. Meanwhile, after a wheel

change Sharon re-joined us. Pretending that

we had just arrived hot and a bit sweaty we

rode into the

school to be greeted by

over 300 cheering kids eager to

plant a tree. Russell Ball did his usual

excellent (tree benefits) talk and children

replied with great answers: each one

rewarded with a ‘Trees are Good’ tattoo. The

teachers, however, did not think this was

such a good idea and were duly told off until

it was explained these are only temporary

transfers!! During the lively debate one

school child even asked if we could stop

Climate Change. With lots of help from little

hands a sweetgum was duly planted and the

Grow Tree Grow chant was sang out in

unison from the surrounding throng of

children. After the chant I could have sworn I

saw a little green bud open close to the stem.

It was then off to the next school via the

famous Chocolate factory in Bourneville.

There was brief photo-call outside the

chocolate factory (no sign of Charlie) and

Peter Wharton kindly nipped into their shop

for some cream eggs. On arrival at Allens

Croft Primary school via another lovely

riparian cycle way we hastily ate said eggs.

The school had a 15 plus knowledgeable eco-

club where many questions about trees were

debated by a switched-on group kids. During

the debate, one child proudly announced that

trees and the oxygen they produce keep him

alive. Needless to say, more deserved Trees

are Good tattoos were given out! A red oak

was planted and Grow tree Grow chanted

with muddy fingers waving at the tree. This

An axe to grind, Pg.53

tree will add to the school’s woodland play

area that the kids have been actively involved

in.

A hearty packed lunch was had at Cannon

Hill Park, with a plenty of lively chatter

amongst the riders set amongst distant views

of to the new Edgbaston Cricket ground.

Keeping to our time schedule we headed

back to the University to plant a

Mongolian Lime with Julian Evans

ICF President. When we arrived,

however, it had already been

planted! But in true

journalistic style the usual

silver-spade snap-shots

were taken.

It was a fabulous day out

in the Birmingham

sunshine, the children as

usual were the stars of

the show. I feel

heartened by their

enthusiasm, tree

knowledge and

environmental awareness.

Let’s hope a few of them

decide that an arboricultural

career is for them.

And the last word from Professor

Julian Evans OBE FICFor, ICF

President:

"Research underpins successful and

sustainable practice. Compared with other

land based sectors, funds devoted to tree

and forestry research are small, yet the

demands from the increasing pest and

disease burden trees face, from climate

change, from the public's enjoyment of trees

and woodlands, to name but three, all bring

challenges. The remarkably successful Ride

for Research in raising funds for the young

charity Fund4Trees is an exemplar of what

can be achieved and what can be a real help.

The Institute of Chartered Foresters is and

remains an absolutely core supporter."

See you on our next Ride – that will tour

through Windsor Great Park – on Sunday

14th

September to coincide with the

AA Conference in Egham.

Thanks to Keith Burgess

(Amey) and David O’Driscoll

(University of Birmingham)

for organising the tree

planting at the schools

and University

respectively; and last but

not least our key-man in

Birmingham for making

it happen – Pete Wharton

The event sponsors;

Acorn Environmental

Management Group,

Capita, Symbiosis, TreeLife

and especially Barcham

Trees for the

trees themselves.

Jonathan Mills:

Senior Arboriculturist Capita

Riders pictured l-r: James White; Andy

Allison; Russell Horsey; Richard Jones;

Jonathan Mills; Sharon Hosegood; Ben

Southhall; Robin Grimes; Richard Round;

Lesley Adams; Russell Ball; Alex Laver and

Pete Wharton . Mick Boddy was taking the

shot!

An axe to grind, Pg.54

Trees in the Hardscape

Making Space for Urban Trees Below & Above Ground

Announcing another great MTOA Seminar.

When and where? 23rd

June 2014 at the Hudson Room, City of York Council Custom-

er Centre, West Offices, Station Rise, York, YO1 6GA (click here for the map location)

The MTOA continue to bring you must attend seminars at treemendous value, please

see below for the details.

The itinerary for the day is;

8.45 – 9.30 Registration

9.30 – 9.55 Moray Simpson (MTOA)

9.55 – 10.35 Martin Gammie (TDAG)

10.35 –10.55 Roy Partington (Infragreen)

10.55 – 11.15 Comfort Break

11.15 – 11.55 Lorna Davis (Welsh Water)

11.55 – 12.40 Steve Chatwin Grindley (Deeproot)

12.40 – 13.35 Lunch

13.35 – 14.20 Dr Roland Ennos (University of Hull)

14.20 – 14.50 Glen Gorner (Leeds City Council)

14.50 – 15.05 Professor Alan Simson (Leeds Metropolitan University)

15.05 – 15.25 Comfort Break

15.25 – 16.10 Dean Bowie (GreenBlue)

16.10 – 16.30 Summing Up & Final Questions

PLEASE NOTE THAT THE PROGRAMME MAY CHANGE ON THE DAY TO SUIT THE SPEAK-

ERS PRESENTATIONS.

All this for only £20, yes £20.00 for MTOA, GYTOG, CAS and ISA members. Non- mem-

bers £65 (dependant on space availability), bookable in advance by contacting Jean

McDermott on 0121 556 8302, enquiries@mtoa.co.uk or write to MTOA, 148 Hydes

Road, Wednesbury, West Midlands, WS10 0DR.

An axe to grind, Pg.55

Advertising in the Axe, members go free!

In 2014 we will be publishing four issues in full colour:

Spring: 12th

February

Summer: 14th

May

Autumn: 13th

August

Winter: 12th

November

If you are looking to advertise then please see the rates below. If you are a member and

wish to place a job advert then this can usually be accommodated free of charge contact the

Editor straight away.

Back page: £250

Inside covers: £200

Full page: £175

Half page: £100

Quarter page: £50

If booking a run of four full page adverts in consecutive issues, then you will receive the

final advert in the 4th edition for free. Advertisers who pay for ads in advance (by the pub-

lication of the first edition the advert runs in) receive an additional 5% discount. Payments

received after that date will not qualify for the prepayment discount.

And finally.

I would like to on behalf of the MTOA wish

Ken Simmons, Forestry Manager of

Warwickshire County Council all the very best

indeed on his retirement.

He not only has served them for best part of

40 years but has served the MTOA pretty

much from day one and will be badly missed,

good volunteers are hard to find.

Ken is pictured left at the recent MTOA

meeting “Hedging your Bets” winning the

raffle, and I hope he takes his lucky streak

with him into his next venture—I

am certain we will hear from Ken

again.

Mac

An axe to grind, Pg.56