Medicinal trees in smallholder agroforestry systems: Assessing some factors influencing

cultivation by farmers East of Mt. Kenya

Jonathan Muriuki Kiura

Presentation summary

The research problemResearch concept and

objectivesStudy area and methodsResults and discussionsConclusions and

recommendations

2

The problem

Indicator Austria

Ethiopia

Kenya

Malawi

Rwanda

Tanzani

a

Uganda

Zambia

Population (2010 est.) mio 8.4 79.5 38.6 15.6 10.4 43.2 31.8 13.3

GDP (US$) trillions (2009) 385 29 30 5 5 22 16 128

GDP per capita US$ (2009)

38,748

936 1,572 859 1,071 1,358

1,219

1,431

Infant mortality rate (IMR) per 1000 births (2009)

4.4 86.9 64.4 89.4 112.4 72.6 76.9 92.7

Under five mortality rate per 1000 births (2009) 5.4 145.3 104.1 131.

8

187.8 118.

4

127.

4

157.0

Maternal mortality rate per 100,000 live births (1999)

NA 870 590 1100 1100 530 510 650

Total fertility rate (2007/8)

1.42 5.29 4.96 5.59 5.92 5.16 6.46 5.18

Literacy rate (2007/8) 99.0 35.9 73.6 71.8 64.9 72.3 73.6 70.6Life expectancy - years (2007/8) 79.8 52.9 54.1 48.3 46.2 52.5 51.5 42.4

Contraceptive use (%) (1999) NA 15(05

)

46(09

)

41(0

8)

36(08

)

26(0

5)

24(0

6)

41(07

)

Majority of Africa population is poor and ravaged by treatable diseases but can’t afford modern medicine

An example of malaria – quick factsFactor StatisticAnnual number of malaria cases globally 247 millionAnnual number of malaria deaths globally 881000Number of malaria-endemic countries 109Number of people at risk for malaria 3.3 billionPercent of global population at risk for malaria 50%Percent of malaria deaths in Africa 91%Percent of malaria deaths in children under 5 85%Percent of symptomatic children under 5 in Africa treated with ACTs

3%

Percent of at-risk people in Africa protected by Insecticide-Treated Nets

26%

Source: World Malaria Report 2008

Who offers treatment in Africa?Country Doctor :

patientTMP : patient

References

Eritrea Doctors estimated at 120 in 1995

Government of Eritrea, 1995

Ethiopia 1:33,000 World Bank, 1993

Kenya 1:7,142 (overall) 1:987 (Urban - Mathare)

World Bank, 1993

1:833 (Mathare) 1:378 (Kilungu)

Good. 1987:

Malawi 1:50,000 1:138 Msonthi and Seyani, 1986

Mozambique 1:50,000 1:200 Green et al. 1994

Sudan 1:11,000 - W Bank, 1993

Swaziland 1:10,000 1: 100 Green, 1985Hoff and Maseko,1986

Tanzania 1:33,000 1:350-450 DSM

W Bank, 1993, Swantz, 1984

Uganda 1:25,000 1:708 WBank, 1993, Amai, 1997

Zambia 1:11,000 - World Bank, 1993

Zimbabwe 1:6,250 1:234 (urban)1:956 (rural)

World bank, 1993Gelfand et al. 1985

Medicine

Plant Knowledge

Phyto-medicines rely on two elements, plants (of which over 60% are perennial trees and shrubs) and

the knowledge associated with their use. Either alone is useless.

Traditional medicine, mainly herbal, has been substantially managing African health but is under threat

6

Herbal medicine relying on wild plants collection is not viable because biodiversity in Africa is threatened by agriculture, urbanization etc and forests lost to below 10% in many countries (e.g. 1.7% in Kenya at present)

Country area (x1000 hectares)FRA 2005

categories Austri

aEthiopi

aKeny

aMala

wiRwanda

Tanzania

Uganda

Zambia

Forest* 3862

13000 3522 3402 4803525

7 36274245

2Forest and other wooded land

3980

576503844

2 3402 5414001

3 47774561

3

Other land4293

519811847

2 6006192

64834

61493

32872

6

Total land area8273

1096315691

4 9408246

78835

91971

07433

9Inland water bodies

113799 1123 2440 167 6150 4394 922

Total area of country

8386110430

58037

11848

2634

94509

24104

75261

% forest of total land area 46.7 11.9 6.2 36.2 19.5 39.9 18.4 57.1% forest of total area of country 46.1 11.8 6.1 28.7 18.2 37.3 15.0 56.4

7Extent of forest and other wooded land in Eastern Africa compared to Austria by 2005

With increasing trade and TM use, medicinal plant resource depletion is abundant and cultivation has been recommended as a possible solution

But that is very easy for herbs (annuals) if appropriate germplasm and products markets are accessible. For trees and other long rotation woody perennials that poses a big challenge due to having to wait long and as long as wild resources are available and perceived to be a common good8

9

Conservation through use under cultivation - What would be the ideal trend of growth in material supply as knowledge of use improves?

Research questions How do socio-economic factors

influence the decisions by farmers to cultivate or conserve medicinal plants?

How does ecology influence use and cultivation of medicinal tree species?

10

Main hypothesis The level of medicinal tree cultivation (Mc) is a factor of germplasm availability (g), species ecology (e – climate, soil and competition), local disease burden perception with appropriate knowledge on use of medicinal trees (k), and availability of market for medicinal tree products (m).

Mc = f(g, e, k, m, α)

Conceptual framework

11

Ge

ne

ral C

on

ce

ptu

al F

ram

e o

n

farm

er

ad

op

tio

n o

f a

n a

gri

cu

ltu

ral

pra

cti

ce A

dapt

ed fr

om F

AO

(20

01)

12

Smallholder production sub-system

Household Consumption

Alternatives

Sold to Markets

Human Capital

Production Technology

Access to inputs

Other Products

Income

Fig. Conceptual framework showing some factors expected to influence cultivation of medicinal trees by smallholder farmers

Germplasm (g)

Medicinal trees (C)

Timber, food, ethno veterinary, etc

Clinical Medicine

Self treatment knowledge (k)

Cultivation ecology (e)

Motivation to plant

(m)Niche defines quality and

interaction with crops (opportunity cost to land and

labour

Seedling quality as well as

access and cost may demotivate

Motivates especially if not extractive harvesting

If alternative perceived better then only this path taken

Wild sourc

es

Demotivates depending on

access and abundance

Objectives

13

1. To collate the perspectives of farmers and herbalists on the factors influencing their preference and cultivation of tree species with medicinal value

2. To assess the influence of local disease burden perception and knowledge of herbal treatment on the efforts by farmers and herbalists to cultivate medicinal trees

3. To explore the contribution of farm grown herbal material to medicinal tree product markets and its effect on medicinal tree cultivation

4. To explore how germplasm access by farmers and on-farm tree nurseries influence medicinal tree cultivation

5. To explore motivational drivers of cultivation and the scope for herbalists’ and traders’ utilization of farm produced medicinal tree products

The study area

14

3 districts (Embu, Mbeere and Meru central)

Population density 100-500 persons / sq km

Nine agroecological zones (LM5 to LH1)

Rainfall – 500 -2600mm;

Altitude 500 -2500masl

Soils – varying from nitisols to ferrasols

Mixed-crop and livestock agric systems

Good tree planting culture

Data collection methodsFarmer group meetings - cultural domain

analysis - 13 groupsIndividual interviews - analysis with SPSS

200 farmers 60 herbalists 60 nursery operators 55 market players in 3 cities

Species abundance surveys in farms, forests and herbalist gardens - analysis with BiodiversityR

Personal observationsTriangulations - interview responses tested

with empirical measurements15

Interview survey resultsMedicinal species present in farms and herbalist gardens

Farms – 295 total species (trees – 45%, shrubs – 27% and herbs – 28%)

Herbalists’ gardens – 203 total species (trees – 40%, shrubs – 27% and herbs – 33%)

60 species known as medicinal by farmers but not recorded in any farm (22 trees, 26 shrubs and 12 herbs)

Do farmers know more species than herbalists????? 16

Medicinal plant species encountered in farms

TreesShrubsHerbs

Medicinal plant species encountered in herbal-

ists' gardens

TreesShrubsHerbs

Factors influencing cultivation

Factor influencing cultivation decision

Farmers’ rating Herbalists rankingFreq.% (n=200)

Mean rate

Freq % (n=60)

Mean rank

Knowledge of treatment 97 2.3 98 4.3Access to medicinal products’ markets 89

1.298 2.9

Germplasm availability 80 1.2 98 2.5Conservation of species that were getting scarce 54

1.298 4.0

Species cultivation technology known 81

1.398 1.4

Other uses of species 19 1.3 2 1

Herbalists knowledge issue was only a species treating many diseases 17

Species highly preferred for cultivation

Species

Growth form Frequency (%) of preference by

herbalists farmers

Prunus africanaTree

56 26

Warburgia ugandensisTree

56 7

Aloe spp.* Herb 49 45

Azadirachta indicaTree

40 47

Olea europaea ssp africanaTree

51 18

Strychnos henningsiiTree

26 9Erythrina abyssinica Tree 35 10

Myrsine melanophloeosTree

23 13Caesalpinia volkensii Shrub 26 14

Zanthoxylum chalybeumTree

12 6

Senna didymobotryaTree

9

Ocotea usambarensisTree

19Croton megalocarpus Tree 12 11 18

Summary on farmers and herbalists’ perceptions

Herbalists preferred trees that treat more diseases and are scarce – farmers knowledge then markets

Farmers in Mbeere influenced by germplasm availability than markets

Multiple use of species not very important to influence both farmers and herbalists

Cultivation technology rated low – but factors such as appropriate niches and farm sizes important

Women farmers rated knowledge, markets and multiple use higher than men

Trees on farm correlated loosely with the frequency of species preference

Usually one tree per household is enough for self treatment and neighbours can use

19

Most socio-economically important diseases

Disease Herbalist s’ score Herb Rank Farmers’ score Farm Rank

Malaria 10.7 1 11.2 1

Typhoid 5.7 7 8.5 2

Respiratory problems 8.3 3 7.9 3

HIV/AIDS 8.6 2 6.7 4

Pneumonia 7.0 4 6.1 5

Hypertension 5.2 9 5.0 6

Tuberculosis 5.9 6 4.4 7

Diabetes 6.1 5 4.2 8

Back/bones/joints aches 3.6 16 4.2 9

Cancers 5.0 11 4.0 10

Measles 3.5 18 3.9 11

Dental disorders 5.3 8 2.8 20

Rheumatism 4.8 13 3.8 15

Amoeba 4.8 12 3.7 16

Asthma 5.1 10 2.6 2420

Disease effect management by farmersHealth management measure Percent (n =142)Preventive (ex ante risk minimising) 232Clean drinking water 30Contribute to development of community health facilities 3Good diets 30Immunization through vaccination 3Keep useful medicine in house 19Keeping warm 4Medicinal plant conservation 51Other preventive methods 1Other traditional health practices 3Personal and household hygiene 57Public health training and practices 1Use of mosquito nets 31

Treatment (ex post risk coping) 32Off the counter medicine 4Seek conventional medicine assistance 3Use of herbal medicine 25

Grand Total 264* 21

Number of species used in treating important diseases

22

Malaria

Pneumonia

Rheumatism

Typhoid

Bones

Amoebiosis

Coughs

Dental

Diabetes

Allergies

0 20 40 60 80 100 120 140

90

40

54

42

37

52

81

37

16

27

HerbalistsFarmers

Highly ranked species in treatment of most important diseases

23

Amoebiasis

Back/joint/ bone problems

Cough/flu

Dental problems

Diabetes

Malaria

Pneumonia

Rheumatism

Typhoid

Aloe sp 6 5 10 3 95 27 8 8Azadirachta indica 2 15 12 2 2 126 10 15 25Caesalpinia volkensii 5 1 49 1 1 2Dalbergia melanoxylon 6 3 2 1 1Erythrina abyssinica 5 6 3 12 5 6 7 4Moringa oleifera 1 2Myrsine melanophloeos 13 3 2Olea europaea 14 32 6 17 1 7 3Prunus africana 4 13 5 3 1 1 1 13Strychnos henningsii 9 2 12Warburgia ugandensis 2 2 8 4 10 2 1

Farmers’ sources of knowledge on use of medicinal plants for disease treatment

Information sourcesFrequency (%) of mention as source number: (N=200)

1 2 3 TotalHerbalists 25 0 0 25Nursery operators 3 0 0 3Media (newspapers, radios ) 6 5 0 10Older relatives (parents, grandparents ) 57 21 4 82Neighbours 7 16 9 32Seminars 1 3 1 5Exchange programmes by NGOs 2 4 1 6No response 2 53 85Total 100 100 100 300

24

Most information passed through genealogy and herbalists contribution is low!

Who speaks about importance of medicinal tree cultivation to farmers?

1st 2nd 3rd TotalHerbalists 11 0 0 11Tree nursery operators 6 1 0 7Media (newspapers, radios) 2 2 1 4Older relatives (parents, grandparents ) 6 1 0 6Neighbours 2 4 3 78Development programmes (govt, NGOs 16 7 1 23Medicinal tree product buyers* 1 1 0 1Own initiative* 14 3 1 17No response 45 84 95

25

So knowledge of medicinal tree species varies with socio-demographic categories

Socio-economic factor 1 2 3 4 5 6 P - value

Gender 12.6 13.2 0.551Age 8.4 10.1 12.9 14.9 14.9 12.7 0.002Education level 16.1 13.2 12.5 11.1 6.6 0.012District 9.2 15.1 13.9 0.000First response to symptom of illness by family member 15.1 10.8 12.2 9.0

26

Key: Gender -1(Female), 2 (Male); Age in years – 1 (<25), 2 (25-35), 3 (35-45), 4 (55-65), 5 (>65); Level of education attained – 1 (not schooled), 2 (primary level), 3 (village polytechnic), 4 (secondary), 5 (post secondary); District – 1 (Embu), 2 (Mbeere), 3 (Meru Central); First response to ailment - 1 (find a medicinal plant), 2 (buy an over the counter drug), 3(consult a medical clinic or hospital), 4 (consult a herbalist)

Number of species known increased with age, district harshness, and use but decreased with education level attained by respondent

Does farmer’s knowledge influence cultivation

27

Ka = All species known and the diseases treated

Kb Kc = Kb with the diseases weighted by the farmer perceived socio-economic importance

All

med

icin

al tr

ee s

peci

es

in fa

rms

Same as Ka

Onl

y pl

ante

d tr

ee s

peci

es

Same as Ka

Kb = Ka plus species used at home weighted by multiplying by 2 – same relationship as Ka

Only number of species used and not total number of trees since farmers indicated that one tree was enough for household self medication for almost all species

Knowledge index a6040200

25

20

15

10

5

0

All med species in farm

LinearObserved

Knowledge index c4003002001000

25

20

15

10

5

0

All med species in farm

LinearObserved

Knowledge index b120100806040200

20

15

10

5

0

All planted med species

LinearObserved

Knowledge index c4003002001000

20

15

10

5

0

All planted med species

LinearObserved

r = 0.7

r2 = 0.5

r = 0.5

r2 = 0.3

r = 0.8

r2 = 0.6

r = 0.6

r2 = 0.4

Summary on farmers knowledge on TM and its influence on med tree planting

No difference in rating of disease economic importance between farmers and herbalists rate -same as hospitals

Medicinal trees play role in household healthHerbalists use more of wild species while

farmers use agroforestry species moreFarmers learn about medicinal trees from

relatives and cultivation mainly own initiativeThe medicinal species present in farms

influenced more by the species known little by the perception of the socioeconomic importance of diseases

28

Medicinal plant markets and cultivation of medicinal trees

29

Business categories

Freq % (n=55)

Av Trade period

Av % annual growth

Av no Species traded

Av % volume purchased

Av %of volume wild

Final products 36 11 424 7 69 29

Herbal Clinic 40 17 158 6 45 59Pre-processing 24 17 100 5 36 72

Grand Total 100 15 241 6 53 51

Herbal clinics

Pre-processors

Final products

Sources of herbal materials in markets

SpeciesGrowth habit

Freq % (n=55)

Av Trade period

Av annual trade (Kg)

Av annual growth %

Av % from farm

Demand trend

Aloe spp Shrub 51 14 286 333 55 Rising

Azadirachta indica Tree 44 14 693 496 88 Rising

Warburgia ugandensis Tree 24 11 333 231 44 Rising

Eucalyptus spp Tree 22 10 117 600 98 Rising

Prunus africana Tree 22 14 408 255 73 Rising

Urtica dioica Herb 20 8 943 1122 30 ConstEkebergia capensis Tree 13 22 105 32 5 Rising

Zanthoxylum gillettii Tree 13 15 175 109 0 Rising

Albizia anthelmintica Tree 9 20 77 75 0 Rising

Kigelia africana Tree 9 5 269 214 30 Const

Moringa oleifera Tree 9 5 463 864 100 Rising

Croton megalocarpus Tree 7 20 168 189 95 RisingRhamnus prinoides Tree 5 6 104 150 33 RisingSenna didymobotrya Shrub 5 12 80 199 33 Const

The numbers show the average per trader for each parameter; n=55

30

Traders’ preference for source of medicinal plant materials

31

Preferred source

Reason for preference % of respondents giving reason

Procurement approach

Farms (27% of respondents)

• Natural resource conservation

5 Own collection

39%

Purchased 61%

• Good tree husbandry in farms

11

• Species authenticity in farms

4

• Species scarcity in the wild 7

• To create market / future sources

2

Total 29

Natural forests and woodlands (69% of respondents)

• Customary preference in practice

2 Own collection

51%

Purchased 49%

• Mature plants and grown in rich substrate

16

• Less contamination/interference

15

• Little or no cost of procurement

7

Total 76

No preference (4% of resp)

• Depends on distance and costs

2 Own collection

100%• No reason given 2

4

But farmers reported little connection to markets

SpeciesNumber of farmers

Plant part sold Where sold

Markhamia lutea 1 Roots Herbalist/neighbours (1)Myrsine melanophloeos 3 Seeds

Vendors (1); Market (2); Neighbours (1)

Olea europaea 2 Cuttings Vendors (2)Osyris lanceolata 1 Whole plant Vendors (1)Warburgia ugandensis 1 Bark Herbalist (1)

32

• Trade in medicinal trees was rising but farmers were not participating in any significant manner

• Most of indigenous tree species were traded collected from the wild – threats

• Two thirds of traders who purchased materials preferred farm sourced materials – mostly in the final products category

• Getting materials at little or no costs contributes to more wild collection – distance may discourage but not tested in this study

Su

mm

ary

on

tr

ad

e

Focus on tree seedling sources District No of

nurseries

Av size (m”)

Space with trees (%)

Embu 20 103 93

Mbeere 20 47 94

Meru Central

20 544 79

Total/Average

60 231 89

33

DistrictPlanted in garden

Given away

sold or given free

Exclusively sold

Grand Total

Embu 7 7 5 5 23Mbeere 3 0 2 0 5Meru Central 5 2 2 3 12Total 15 8 8 8 40

Herbalists with nurseries (numbers are % n = 60)

Em

bu fo

dder

Em

bu fr

uits

Em

bu m

edi

cina

l

Em

bu ti

mbe

r

Mbe

ere

fodd

er

Mbe

ere

frui

ts

Mbe

ere

med

icin

al

Mbe

ere

timbe

r

Mer

u fo

dder

Mer

u fr

uits

Mer

u m

edic

inal

Mer

u tim

ber

District and category of tree species

0.0

2.5

5.0

7.5

10.0

Nu

mb

er

of

tree

sp

eci

es

in n

urs

ery

Presence of highly preferred species in nurseries

Species

Growth habit

Freq % (n = 60)

Av no seedlings

Av seedlings supplied before

Av trend Demand

Prunus africana T 25 211 1111 H

Azadirachta indica T 13 37 43 H

Olea europaea T 12 292 1477 H

Aloe spp. H 8 101 61 HCroton megalocarpus T 8 7 46 C

Juniperus procera T 8 406 2223 HHagenia abyssinica T 7 4 108 HCroton macrostachyus T 5 0 87 C

Markhamia lutea T 5 305 93 CMyrsinne melanophloeos T 5 668 3438 HAcacia xanthophloea T 3 5 33 C

Bridelia micrantha T 3 0 25 H

34

Sources of medicinal trees in farms

Species% farms NR

Neighbours

Tree nurseries

Wildlings

Aloe sp 52 17 6 5 64

Azadirachta indica 27 9 4 59 6Croton macrostachyus 24 48 2 17 29

Prunus africana 23 24 2 22 50Senna didymobotrya 21 67 2 2 21Croton megalocarpus 20 3 3 48 35Erythrina abyssinica 20 68 3 3 25Tithonia diversifolia 19 24 8 0 62

Olea europaea 17 41 3 12 35

Psidium guajava 16 10 3 48 23

Solanum incanum 13 96 0 0 4

Terminalia brownii 11 81 0 5 14

Ocimum suave 10 80 5 0 10Zanthoxylum chalybeum 10 90 0 0 10

35

Summary on seedling sources

• Farmers were mainly planting medicinal trees from wildlings

• Demand for medicinal species lower than timber and higher than fruits and fodder in Meru; lower than fruits and fodder in Mbeere and fruits in Embu

• Demand for medicinal seedlings higher than supply in nurseries – but not all species

• Need investment in diversifying germplasm in both private and herbalist nurseries

36

Key species abundance surveys (focus on 30 most preferred)

Forests and woodlands (herbalist in team)Species abundanceAge/size distributionsEvidence of harvesting

method damage

37

Farms In twenty farms and ten

herbalist gardens in each district

Key species abundance Age/size class distributions

relating to regeneration method

Niche in the farm Other competing household

or market uses of the species

38

Species abundance survey results

The thirty species were whose abundance was measured include

Albizia gummifera Ficus sycomorus Rhamnus priniodes

Aloe sp Ficus thonningii Ricinus communis

Azadirachta indica Kigelia africana Senna didymobotrya

Brideria micrantha Leonotis mollissima Solanum incanum

Ceasalpinia volkensii Moringa oleifera Strychnos henningsii

Cordia africana Ocotea usambarensis Tithonia diversifoliaCroton macrostachyus

Myrsine melanophloeos Vepris nobilis

Croton megalocarpus Osyris lanceolata Warburgia ugandensisDalbergia melanoxylon

Olea europaea ssp africana

Zanthoxylum chalybeum

Erythrina abyssinica Prunus africanaZanthoxylum usambarense

39

General abundance of species in surveyed farms, forests and herbalists’ gardens

Rank

Farms % Prop

Herbalists‘ gardens

% Prop

Forests % Prop

1 Eucalyptus spp

11.3 Lantana camara

16.4 Sizygium guinense

8.7

2 Grevillea robusta

10.0 Catha edulis

9.2 Mugiru

7.8

3 Catha edulis

9.4 Solanum incanum

9.1 Mwenyuka

6.4

4 Solanum incanum

9.1 Erythrina abyssinica

6.8 Mukwethe

2.9

5 Acacia tortilis

6.0 Leucaena spp

6.4 Mutengerethe

2.9

6 Acacia spp

3.2 Grevillea robusta

3.2 Aspilia africana

2.7

7 Acacia brevispica

3.2 Indigofera lupatana

3.1 Gnidia subcordata

2.6

8 Lantana camara

2.9 Acacia nilotica

2.9 Lantana camara

2.4

9 Tithonia diversifolia

2.9 Acacia tortilis

2.6 Murieni

2.3

10 Aloe spp

2.6 Maytenus senegalensis

2.6 Ocimum suave

1.8

40

30 top species accumulation curves

41

5 10 15 20

05

10

15

20

sites

sp

ecie

s r

ich

ne

ss

Embu

Embu

Mbeere

Mbeere

Meru

Meru

2 4 6 8 10

05

10

15

20

25

sites

sp

ecie

s r

ich

ne

ss

Embu

Embu

Mbeere

Mbeere

Meru

Meru

5 10 15 20

05

10

15

20

sites

sp

ecie

s r

ich

ne

ss

Embu

Embu

Mbeere

Mbeere

Meru

Meru

Forest and woodlandsMbeere Embu Meru

Smallholder farmsMbeere Embu Meru

Herbalist gardens/farmsMbeere Embu Meru

• More abundance in forests and woodlands in Mbeere than Embu and Meru

• Herbalists in Embu and Meru plant more – response to scarcity

• Not much difference in abundance in smallholder farms in the three districts but smallholders generally plant less

20

25

20

20

10

20

Speci

es

rich

ness

Speci

es

rich

ness

Speci

es

rich

ness

Sites

Sites

30 top species Renyi profiles

42

0 0.25 0.5 1 2 4 8 Inf

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

alpha

H-a

lpha

Farmers

Farmers

Forests

Forests

Herbalists

Herbalists

0 0.25 0.5 1 2 4 8 Inf

0.0

0.5

1.0

1.5

2.0

2.5

3.0

alpha

H-a

lph

a

Embu

Embu

Mbeere

Mbeere

Meru

Meru

Forests and districts

0 0.25 0.5 1 2 4 8 Inf

0.0

0.5

1.0

1.5

2.0

2.5

3.0

alpha

H-a

lph

a

Embu

Embu

Mbeere

Mbeere

Meru

Meru

Herbalists and districts

0 0.25 0.5 1 2 4 8 Inf

0.0

0.5

1.0

1.5

2.0

2.5

3.0

alpha

H-a

lph

a

Embu

Embu

Mbeere

Mbeere

Meru

Meru

Farms and districts

Combined

0 0.25 0.5 1 2 4 8 Inf

0.0

0.5

1.0

1.5

2.0

2.5

3.0

alpha

H-a

lph

aFive

Five

Ten

Ten

Forests and distance RP

0 10 20 30 40

05

10

15

20

25

sites

spe

cie

s ri

chn

ess

Five

Five

Ten

Ten

Forests and distance SAC>5 km from village <5 km from

village

Mbeere Embu

Meru

Mbeere Embu

Meru Speci

es

rich

ness

25

H-

alp

ha

H-

alp

ha

H-

alp

ha

H-

alp

ha

H-

alp

ha

Age and Dbh class comparisons

43

• More planting by herbalists in the lower age classes than farmers

• More lower size classes in farms than forests• But farmers only 30% of the species were said to be

primarily for medicinal use by farmers compared to 66% by herbalists

Mean proportion of tree numbers planted by Age class Farmers Herbalists Average F Sig 0-5 19 56 36 104.8 0.00 6,0-20 8 24 15 34.3 0.00 20+ 2 5 4 4.0 0.04 NR 71 15 45 259,6051 0.00 Size class Mean proportion found in Farms herbalists Forests Average F sig 0,5 - 4,9 19 22 8 17 7.10 0.00 5,0-9,9 57 53 45 52 3.51 0.03 10-19,9 13 12 13 13 0.21 0.81 20-39,9 7 9 15 10 5.91 0.00 40+ 3 5 19 8 22.28 0.00

* numbers represent the average of the proportion of the trees in the age/dbh category to all the trees of each of the study species in the farm/plot

Is there potential for herbalists and traders to use farm-grown

herbal material in future?

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Cluster analysis based on ecological preferences for herbal medicine raw material sources by herbalists and traders

Item Parameter Cluster centres

1 2 3 4General ecological perception

Believes ecology affects medicine quality 2 2 2 2Prefers farm (1) or forest (2) source 2 1 1 2Prefers humid (1) or dry (2) source 2 2 0 2Prefers cool (1) or warm (2) source 2 2 0 2

Perception of farm as only source

Prefers isolated (1) or many (2) trees 1 1 0 1Prefers fertile (1) or infertile (2) site 1 1 0 1Prefers open (1) or shaded (2) sites 1 1 0 1

Preference for improved medicinal tree ideotype*

Mean score for fast growth rate 3 4 3 2Mean score for resilience with constant harvesting 2 3 3 3

Mean score for high chemical composition 2 2 3 4Mean score for high biomass production 4 1 2 1

Percent of respondents in clusters

Herbalists (n=60) 15 22 17 43Traders (n=55) 51 25 2 22Total 32 23 10 33

Options for ideotype improvement preference:- 1. Least important; 2. A bit important; 3. Important; 4. Most important

Summary findings on species abundanceHighly preferred medicinal trees were more

abundant and even in herbalist gardens than farms and forests

There were more lower age and size classes in herbalist gardens hence diversity may increase in future

Herbalists planted more in areas where diversity was less in forests

There were no specific niches that mimicked forests that herbalists preferred to plant medicinal trees

More herbalists and traders preferred medicinal trees sourced from forests but not necessarily farm niches that mimicked forest situations

Upto 67% of the current traders and herbalists can switch preference to farm grown herbal material if forest trees were not very accessible

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General conclusionsFarmers maintain medicinal tree species on

farms for household health insurance – only one tree is enough per household

The more trees known the more conserved Herbalists not engaged in conservation

advocacy and young and educated farmers least informed

Herbalists cultivation is increasing as a response to scarcity – good entry to ensure diversity in farms

Trade in medicinal trees’ products is growing and could stimulate cultivation

Strategies needed to support nurseries in dry areas as current abundance will disappear fast

Empirical measurements supported survey responses

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Recommendations - actions

Involve herbalists and tree nursery operators in extension on medicinal trees information

Further development of markets and link to farmers

Policy incentives to promote cultivation and discourage wild collection

Germplasm conservation and production linking herbalists and nursery operators

Policies to develop arid areas as future sources of medicinal tree material

Further research on influence of various cultivation approaches on medicinal tree active component concentration

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Multi-stakeholder approach needed to collate and share information with farmers on•Useful medicinal species for what diseases

•Markets needs (MIS)•High quality germplasm sources•Appropriate cultivation technologies

Recommendations - top species for domestication priority – matrix ranked

Azadirachta indicaAloe spWarburgia

ugandensisCaesalpinia volkensiiPrunus africanaZanthoxylum

chalybeumStrychnos henningsiiSenna didymobotryaMoringa oleiferaDalbergia

melanoxylon

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Leonotis mollissimaCroton

macrostachyusCroton

megalocarpusOlea europaea ssp

africanaPsidium guajavaOsyris lanceolataPlectranthus

barbatusErythrina abyssinicaRhamnus prinoides• Fagaropsis

angolensis

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Senna didymobotrya Azadirachta indicaDalbergia melanoxylonOlea europaea ssp

africana

Warburgia ugandensisAloe sp

Moringa oleiferaZanthoxylum chalybeum

Acknowledgements

• Prof. Gerhard Glatzel• Prof. Christian Vogl• Profs. From IFE : Gratzer, Hager and others• ICRAF senior staff: Drs. T. Simons, S. Franzel,

R. Jamnadass• OEAD• ICRAF administration and GRP1 colleagues• Fellow students and IFS staff• My family (Esther, Grace, Victor)• Extended family and friends• et al

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And many thanks to you all for attending

and listening

‘If many little people, in many little places, do many little things, they can change the face of the earth.’