Catskill High Elevation Forest Continuum

8/4/2019 Catskill High Elevation Forest Continuum

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The Catskill Mountain High ElevationForest Continuum

Matt Heimel

Geography 399 Independent Study: Advanced Biogeography

SUNY Oneonta Summer 2011

Wittenberg Mountain, the Central Escarpment, and the Blackhead Range beyond, as seen from Cornell Mountain.


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1. Introduction

Earth and the life that inhabit it have evolved together. Continents are continuously being

reshaped, and the form a landmass may take has reaching effects into the future. Regional ecosystems

throughout natural history must sustain themselves and adapt to the changing physical restrictions within

their habitat, and the genetic links that survive are the key to what adaptations and life forms will be

characteristic to the future forms of the planet. These statements may be applied to the Catskill

Mountains; these relatively small mountains are the depository remnants of a once towering mountain

range. Ecology of the ancient delta, evidence of which is recorded in the bedrock strata, reveals

alternating patters of shallow seas, floods, and riparian systems altered by evolving vegetation. Lifes

adaptations to survive in the ancient environment are links to modern life forms for parallel present

environments. Continental glaciations had a major role in further eroding the mountains and adding final

touches. The progressive return of vegetation after glaciations shows a primary succession pattern

following a denuded landscape, leading to a summit forest community displaying characteristics of the

boreal forest ecosystem, presently undergoing a gradual transition to a hardwood community.

The vast, ancient depositional delta has eroded away through glaciations and flowing water.

Highest elevations in the Catskill Mountains are what remains of lesser-transported alluvial deposits. That

zone is the habitat for the spruce-fir assemblage of the Catskill forest community, a part of the eastern

forest biome. The purpose of this study is to present a comprehensive biogeographical natural history and

analysis of the dominant forest ecosystem factors for the highest elevations in the Catskill Mountains. The

five highest mountaintops were chosen as sample plots for discussion because they represent an ultimate,

limiting parameter to vegetational development within the entire Catskill ecosystem. Dominant over,

middle, and under stratum species are determined and their adaptations and factors for distribution are

discussed. Environmental factors at these elevations are unique from the lower elevations because of the

regions topography and history, and dominant species of vegetation respond to these differences.

2. Geographic Location & Environment

The Catskill Mountain ecological sub region discussed in this paper is the northeastern inclusion

of the geomorphological Appalachian Plateau province. Structurally it is a maturely dissected plateau,

with flat mountaintops separated by weathered drainage channels and basins [figure 2-1]. On its eastern

front, there is a 2,000 to 3,000 steep escarpment into the Hudson Valley [figure 2-2]. On the western

front, there is a gentle merge into a hilly landscape typical of the western Catskill region and the

Allegheny Plateau [figure 2-3]. Within the Allegheny and northeast Appalachian Plateau regions, the


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Catskill Mountains have the highest elevations, ranging

from ~900 to 4,182 feet. Most of the terrain is steep, with a

typical steppe like pattern comprised of sandstone ledges

with intermittent slopes containing boulders and glacial till

under organic soils.

The forests on the five highest mountains were used

as sample plots representing the climax spruce-fir

ecosystem. These relatively small areas of forest cover

were chosen because they represent the highest reaches of

elevation on individual mountains. Although the area is

structurally one dissected plateau, each slope has

undergone distinct vegetational migrations to the top

following a post-glacial primary succession pattern. There

are mountains below the five highest elevations that share

the same spruce-fir communities, and some dominated by

hardwoods. The theory presented here is that these

communities are distributed independently of elevation,

precipitation, and temperature, and the presence of spruce-

fir forests is attributed to the soil conditions. The five

highest elevations will provide an analysis of what species

dominate those mountains, and the physiographic site

characteristics can be inferred by what species are present.

2a. Climate

The Catskills are within a severe mid-latitude

climate. Temperatures change along a wide spectrum between warm, humid summers and severely cold

winters. Precipitation decreases during the winter months, but overall it is evenly distributed throughout

the year [figure 2-4]. The prevailing westerlies, from the southwest, are the main wind belt for

atmospheric systems in the area. However, seasonal storms such as hurricanes or tropical storms

occasionally reach the Catskills and bring heavy outbursts of precipitation, contributing to flooding and

erosion of riparian areas (Thaler, 1996).

Figure2 1

Figure2 2

Figure2 3


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While the prevailing winds and

atmospheric circulatory patterns bring

the overall climatological classification

to the Catskill region, the primary

differences in localized climate between

mountains are caused by local variations

in weather patterns. Occurrences of

upsloping, downsloping, and the

orographic effect are patterns that

dictate temperature and precipitation differences. The

central Catskill Mountains containing the major

escarpments, and the southwestern mountains with

their intense drainage basins, receive greater rainfall

than the lowlands, as air is forced to rise over the

mountains, cools, and is unable to hold its moisture (Thaler, 1996). Annual

precipitation averages for the valleys ranges from 40 to 48 inches, while it can exceed 60 inches on the

higher mountains, contributing to the extremely lush vegetation and the abundant streams [figure 2-5].

Growing seasons can last between 120 to 160 days, decreasing as elevation increases, which is

evident in the apparent greening of mountain slopes during spring (USGS, 2003). Snow and ice can

remain on the higher mountains through April while plant growth has begun in the lower valleys. Ice and

high winds are a significant disturbance regime in the Catskill forest, commonly causing localized tree

mortalities but stand blowdowns do occur either associated with the heavy buildup of ice or soil and root

saturation (Johnson, 2007).

2b. Soils and Vegetation

Edaphic characteristics of the higher elevation forests are the result of their geological, glacial, and

vegetational histories. The parent material is primarily conglomerate sandstone in the higher elevations.

Over the course of thousands of years, freeze-thaw action and deposition by glaciers has created a mineral

layer or bedrock fractures that vegetation may grow upon once sufficient organics accumulate.

There is no well-developed soil profile present in the higher forests and soils are generally a thin

layer of organics overlying substrate. A mixture of inceptisols and spodosols are present, where the

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Precipitation, in. Temperature, deg.F

2-4: Climograph for higher elevation areas.

Source:NCDC TD 9641 Clim 81 1961-1990

Normals

2-5: Annual

Precipitation map

for Catskill

region. Higher,

southwestern

mountains receive

above 60 inches.

Source: NRCS


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recently glaciated landscape has been denuded of organics and the organic accumulation is still underway

(Kudish, 1979).

The quantity of glacial till is a primary deciding factor in what tree species has been able to

dominate an area (Kudish, 1979). In the high elevation forests, balsam fir, red spruce, and occasional

paper birch are a community preceding hardwood establishment. These species have a lower required

glacial till thickness, and the tops of the Catskill mountains have the thinnest till in the region. The

summits typically have less than 8 inches of till overlying bedrock, if any (Mcintosh, 1962). As the

organics accumulate over hundreds of years to build up humus layers, hardwood species are able to

tolerate the new deeper thickness and establish root systems. The pH of glacial till is a nill factor, while it

is mildly acidic throughout the mountains and does not affect tree species distribution (Kudish, 1979).

High elevation forests are principally growing mineral soils derived from conglomerate

sandstones. The higher amounts of precipitation in these areas creates greater amounts of leaching,

allowing better-developed podzols with an organic mat 2 to 8 inches thick (Kudish, 1971). Water

retention in these soils varies and is attributed with different forest covers. Generally, red spruce

dominance is in an area with high water retention while balsam fir is in areas with lower water retention.

Overall, the water retention in high elevation forests capacity is high (Mcintosh, 1962). The organic soils

covered by a dense mat of sphagnum moss retain the water, and some boreal bog-like conditions are

sustained through the intact manner of the spruce-fir high elevation ecosystem (Larson, 1980).

3. Catskill Paleogeography

Ecological processes of the Catskill forest take place upon depository remnants of ancestral

continental landforms. The Acadian mountain range orogeny is the main geological event that reshaped

the northern Appalachians of which the Catskills are a part. This occurred during the late Devonian period

beginning ~375 million years ago and continuing and for another 50 million years, and later another uplift

in the Late Paleozoic pushed the Catskill basin higher to its current position, weathering away ever since.

During the Devonian period, the earths crust was folded and deformed to form the Acadian

mountains. This occurred through lateral plate compression from the ancestral tectonic Avalonia

and Laurentia plates, where Avalonia was pushed over and accreted to Laurentia. The long series

of uplifts and volcanic centers throughout the extremely large mountain range would have released clastic

rocks, slowly breaking down away the Acadians (USGS, 2003). While the tectonic collision proceeded,

the subsidence pressure created by the increased mass of rock along the mountain chain created an impact

formation known as the Catskill basin to east and north of the Acadian mountains (Murphy, 2006). Today,


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63-2: Alternating layers of sandstones, conglomerates, and red sandstone conglomerates

indicate diverse periods of stream flow intensities to carry different sized deposits.

the basin would encompass parts of northern New Jersey,

southeastern New York, and eastern Pennsylvania. The

Catskill basin, because of its proximity to the Acadian

highlands, would have received the bulk of clastic rock

from the mountain weathering, while farther to the east an

epicontinental sea would have ultimately received the

basins meandering streams and extremely fine grained

sediments [figure 3-1].

Precipitation drainage from the continuously

eroding Acadian mountains was the principal source for

the accumulation of the Catskill delta (Titus, 2004). The

new land shelf widened over time, and a medium grade of

deposition has been noted in the Alleghany and northern

Appalachian regions of which this formation comprises (USGS, 2003). Closer to the rough boundary of

the Hudson River to the former Acadian Highlands is where the greater Catskill Mountains formed. Their

larger size than the rest of the region is attributed to their composition of primarily sandstones and

conglomerate on the higher mountains, which is much more resistant to weathering than the farther and

more distributed clays, siltstones, and shale that make up valley bottoms and the western Catskill and

Alleghany regions (USGS, 2003). The sedimentary basin eventually reached an elevation of ~7,000 feet.

The depositional landmass along the eastern edge, where the

higher mountains are located, had the thickest accumulation of

sediment with exceptionally high concentrations of

conglomerate and sandstones when compared to the rest of the

deltaic clastic-wedge region (Titus, 2004).

The deposition of Catskill delta material was a complex

series of fluctuating shorelines and flood environments. The

landmass progressively moved north, originating in an area

south of the equator. Its shifting position through the equator

climatological zone caused it to experience shifting weather

patterns (Titus, 2004). This is recorded in alternate layers of

deposited sandstone and shale strata, where there are distinct

boundaries between times of deep flood sequences and average

3-1: The Acadian source area eroded, and its

sediment distribution is traced with a relationship

between distance carried and alluvium size.

Source: USGS


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stream flow deposition [figure 3-2]. High seasonal rainfall in the Acadian highlands would have formed

braided, meandering streams throughout the delta. Before vegetation was able to stabilize the region,

broad, shallow, interconnected streams traversed the alluvial plane. These channels were very unstable,

consisting solely of fine sediments and coarser sands that could be constantly shifted in response to

changing stream currents. This created a challenging aquatic and riparian habitat, as the continually

shifting sediments would hamper root development and organic matter accumulation (Murphy, 2006).

Depositional patterns from the later Devonian period indicate a stream flow pattern more akin to

meandering channels (Murphy, 2006). In such a system, the water is confined to a single channel that

slowly erodes its banks. These banks are usually kept stable by streamside vegetation, and the presence of

these streams would suggest that the vegetation during this era had adapted to the alluvial plane

environment. The Devonian era is also attributed to the emergence of deep-rooted trees, which would

have aided in the stabilization process to create meandering stream channels (Titus, 2004).

As terrestrial vegetation became able to establish itself along the waters edge, some of the first

descendants of modern forests began to appear. The genusArchaeopteris has been found in fossil records

in most Devonian landmasses, including a Catskill site located along the Schoharie Creek in Gilboa

(Titus, 2004). Mature stands of this tree would have created a leaf canopy, moderating the temperature

and moisture regimes and creating a shelter for any invertebrates and microbes present. Morphologically,

Archaeopteris would have resembled a modern fern, only much larger, growing

up to 90 feet and living for 40-50 years [figure 3-4]. The new forest possessed

adaptations allowing it to survive in and stabilize its environment, and leaps in

evolution created a forest ecosystem that can be characteristically linked to

modern forests (Murphy, 2006).

Many of the late Devonian plants that grew in the new forests are

regarded as the ancestors of seed plants. Reproductive and vegetative growth

features are shared, such as the branching clusters common to vascular plant

anatomy (Titus, 2004). It is not completely clear which species creates the link

to modern forest and Devonian, but the ancient forest ecosystem is a picture of

one moment in the evolutionary progression towards the modern forests.

4. Present Day Structure of the Catskill Mountains

After millions of years of deposition, uplift, and erosion, the Catskill Mountains are now in their

modern form. Sedimentary rocks, formed by the river deposits in the ancient Catskill delta, lay stratified

3-4: Archaeopteris. Source:

Devonian Times


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in a single plateau, that has been dissected through

complex phases in glacial advances, glacial melt water

surges, and mass wasting through stream flooding.

Where ancient streambeds distributed their deposits,

depending on weight, is outlined by the weathering

resistant ledges surrounded by eroded valleys. Higher

mountains consist of conglomerate and sandstone,

which would have been deposited in river channels

as coarse sand and pebbles [figure 4-1]. In valley

bottoms around the larger mountains where

significant erosion has taken place, beds of soft redshale are often found [figure 4-2]. These are

depository remains of ancient soils, paleosols, and are

what is left of the Devonian forests (USGS, 2003).

Wherever an escarpment is exposed for a

relatively long part of its length, it is evident that there

is one large mass of sandstone that has been subjected

to great stress. This is indicated by the presence of intersecting layers of sandstone and joint fractures

[figure 4-3]. During the Alleghanian Orogeny 330 to 225 million years ago, the Catskill delta was uplifted

to become its current plateau (USGS, 2003). In the many years

since the rock has been eroding away, following these fractures.

Multiple channels became streams as precipitation traveled down

the plateaus developing drainage basins.

This has been the erosional pattern for the Catskill

Mountains, where there is one relative plateau elevation across thegreater Catskill region consisting of dense conglomerate

sandstones, broken down into central drainage basins. Three main

escarpments comprise the mountains- Slide Mountain and its

surrounding ridge, Hunter Mountain and the surrounding central

escarpment mountains, and the Blackhead range. Each range is

4-1: Sandstone outcropping on the summit of Black Head.

4-2: Valley bottom soft red shale, eroded by a nearby

stream, under a large sandstone outcrop.

4-3: Massive sandstone wall on Hunter

Mountain over Stony Clove (figure 5-2)


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separated by large valleys that act as major

watersheds for all of the stream water.

Each Catskill Mountain has a common form.

The summits are plateaus, surrounded on all sides by

steep slopes to the valley bottoms [figure 4-4]. There

are gentler spur ridges coming off of the summits,

reaching down to the valleys [figure 4-5]. Between

these ridges are the steeper slopes, with channels and

streams in the centers. It is this common characteristic

that makes the Catskills recognizable as a single

landform unit that has been carved into individual

sections by water and ice. It takes a stretch of the

imagination to conceptualize what forms the mountains

would take without the vegetation, soil, and glacial till

cover.

5. The Effects of Glaciers

During the Pleistocene Epoch of the past 1.6 million years, there have been cyclic ice ages leaving

dramatically altered landscapes as they retreat. The exact forms that the Catskill Mountains took after

each continental ice sheet is unknown, and recent glacition alters the evidence of past glaciations. The last

ice sheet to have had a great effect on the Catskill Mountains was the Wisconian Stage and later scattered

alpine glaciations. ~21,000 years ago this ice sheet would have reached its maximum thickness of over

one mile, completely inundating the Catskills with a sea of ice, and its retreat from the region would be

well underway by ~12,000 years ago (Titus, 2003). This relatively recent event has set conditions for

revegetation patterns and large-scale flood erosion in the modern world.

During the glaciations, the massive slabs of Catskill sedimentary bedrock were abraded and

quarried. Erosion was greatly accelerated by the sheer volume of ice, and the mountains were broken

down into a mixture of rocky fragments varying in size. The advance of glaciers through the valleys and

eventually over mountaintops has left characteristic U-shaped valleys [figure 5-1].Along the eastern

escarpment wall over the Hudson valley, there are two deep cuts into the mountainsides where the

4-4: Cornell & Wittenberg mountain with the characteristic

plateau and steep slopes of every Catskill mountain.

4-5: Spur ridge off the summit of Black Dome


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glaciers are thought to have made

an advance into the mountains

(Titus, 2003). These areas are

Platte and Kaaterskill cloves,

characterized by steep rushing

streams with headwaters at 2,000

feet above the lower valley

floors. Because these two valleys

were deeply cut by advancing

glaciers and eroded into a main

route or gully, they received

much of the melt water once

glaciers retreated and are two

major drainage routes for the

eastern escarpment.

As the climate began to

warm, the Pleistocene ended, and

ice sheets covering the Catskills

were melting and eventually full

deglaciation occurred. Some

lobes remained for a slightly

longer duration in higher

mountain elevations as alpine

glaciers, creating complex

obstacles for melt water and

revegetation (Rich, 1906). Melt

water from the glaciers became a

principal agent of erosion and

deepened many of the central

drainage basins that are prevalent today. The melting process was an array of ice dammed lakes and

raging melt water torrents. Remaining lobes of ice in the mountain valleys blocked the central drainage

basins, and water levels reached a critical point where they could pour over and cut through a valley

* * ** * * * * * **

5-1: U-shaped Spruceton Valley. Along the north of the central escarpment, this

map shows the hollowed nature of the valley from a glacier tat once pushed

through it.

5-2: Topographic view of the deep notch between Hunter and Plateau mountains,

created by a surge of meltwater that was impounded by a glacial lake.


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5-3: One of the many gorges in the southwestern

Catskills, established through glacial melt torrents

and fed by abundant orographic precipitation.

(Titus, 2003). This process created localized, deep-cut notches

between the higher mountains [figure 5-2]. The localized lakes would

have reached elevations between 1300 and 3200 feet, inundating most

of the Catskill region (DEP, 2009). The same lobes of remaining ice

that created lakes were blocking the central drainage areas. This

diverted water through the southeastern valleys near Slide Mountain,

and many gorges were deepened in the southeastern most extension of

the Catskills (DEP, 2009). The drainage channels between ridges in

this area, characteristic of every mountain discussed earlier, are

exceptionally weathered, with deep ravines showing signs of intense

water erosion as the high amounts of melt water was sent through this one region [figure 5-3].

Periods of glaciations in the Catskill Mountains have worked to accelerate erosion of the

sedimentary bedrock, and deposited glacial till throughout the mountains to reorganize the soil regolith

regimes. The Catskill forest has been recovering from this recent significant period that has greatly altered

the landscape. The forest communities that have migrated and established mature climax forests in the

mountains follow a pattern of facultative seral succession, where the physical limitations on life are

altered as the ecosystem develops. In the following sections, the high elevation forests and their species

are evaluated to determine their ecological niche and roles and how the characteristics of todays forests

will be explained.

6. High Elevation Forest Community Analysis

A sampling method was used in order to establish a sound reasoning and analysis for what species

may be discussed as dominant vegetation. A line transect crossing the highest elevation of each mountain

was used, spanning only the highest area and beginning and ending once the elevation started to slope

down from the summit. These transects were evaluated to determine a) if any vegetational change could

be found that can be attributed to slope or aspect b) Which species were encountered in a frequency or

basal area that determines whether or not it is a dominant characteristic species.

The fact that the sample plots are extremely small when compared to the vegetational area and

ecosystems of the mountains has been recognized. The objective of this analysis was to determine what

vegetational systems are dominant and functioning on the highest elevations only. The hypothesis used

during sampling and analysis treats the high elevation assemblage as a sub-system of the entire forest

ecosystem. The natural history and present day condition of the Catskill high elevation forest community


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can be discussed in terms that are consistent with the entirety of the region. A uniform environmental

system has been met with adaptations from species that are best suited for unique physiographic regions.

6a. Slide, 4182 [figure 6-1]

The summit of Slide Mountain is dominated

by balsam fir, growing to their maturity and there

are abundant saplings to continue its dominance.

There were no seedlings of other tree species

present. A dense mat of moss was the primary

understory, while the typical understory herbaceous

species were scattered. Those species have an

affinity for undisturbed humus, and highest summit

area of Slide Mountain is disturbed. The entire length

of the summit transect, leaving out the side slopes, ran

across some form of soil compaction. The actual

highest point is bare substrate with the cement

remnants of an observation tower base, and a well-

worn hiking trail runs across that point. A small

clearing with a sandstone outcrop exists in one portion

of the summit [figure 6-2]. Balsam fir surrounds the

meadow that is grown in with grasses and scattered

paper birch and mountain maple saplings. In the

surrounding forested area, numerous campsites that show

evidence of past heavy use have left compacted soil and

burnt micro sites. However, areas with tighter balsam fir

growth have hindered the development of campsites. The

balsam fir canopy shades these areas and provides a

relatively undisturbed micro site where there is extremely

thick branch growth. Inspection of these more protected

6-1: Slide Mountain as seen from Cornell Mountain

6-2: Clearing in the summit area of Slide.

6-3: Natural disturbance area on Slide.


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area shows that even in these sites there is no well-developed understory herbaceous layer.

Slide Mountain has a very long southwestern spur ridge on a gradual grade. The summit forest

continues down this ridge, and is much more intact than the highest portion summit area. However, there

is intrusion by hardwoods where paper birch and mountain ash have established themselves in the lower

canopy. The understory herbaceous community here is well developed and healthy.

Within close proximity there is a blowdown area where most of the mature balsam fir have been

killed off [figure 6-3]. There is very thick growth of balsam fir saplings, and mountain ash and paper

birch saplings are also widespread in this area and will likely grow to their maximum. Slide Mountain is

very prone to such events, as its summit is the highest and most exposed in the region. It also receives

over 60 inches of annual precipitation a year, far higher than the surrounding lowlands (USDA/NRCS).

This contributes to the extremely lush undisturbed sections of the summit forest.

6b. Hunter, 4046[figure 6-4]

The summit of Hunter, like Slide, is

extremely disturbed. Numerous clearings of the

summit and the construction and maintenance of a

fire tower have left noticeable impacts on the forest

community. The actual summit, marked by a

boulder, lies within a cleared field for a fire tower.

A ranger cabin is present, while grasses and

spruce/fir saplings are reclaiming the clearing. The

transect line for the forest analysis was started on

the edge of the meadow where the summit

continues along a plateau, while the other side of

the meadow would dip down eventually sloping

towards the valley bottom.

Balsam fir, paper birch, and red spruce are

the three tree species present on the summit [figure

6-5]. Their relationship is evident in their

distribution. Some mature balsam firs are present,

but across the summit there are mostly medium

sized red spruce. Red spruce has the tendency to act

6-4: Hunter Mountain as seen from Plateau Mountain

6-5: Hunter Mountain summit forest.


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as a pioneer species in the event of a clearing if soil

conditions permit its establishment. Many of this red

spruce are dying off, with their top halves blown off

by wind. The middle story is made up of very thick

balsam fir saplings, which were able to germinate in

the partial shade created by the open red spruce

canopy. Spread throughout this area are occasional

paper birch, which are dominant trees all throughout

the slopes of Hunter mountain and have been able to

successfully establish themselves on the summit. It is likely that the balsam fir will grow to maturity and

dominance, red spruce will maintain its presence, and paper birch will remain as a codominant member of

this summit forest.

The understory communities that are typical to the Catskill higher summits, whose species are

described in the following sections, were abundant on Hunter Mountain. Unlike Slide, the anthropogenic

disturbance has not left a long impact on the soil conditions for the large forested summit area, and the

moss and humus layers have been able to develop successfully

[figure 6-6].

6c. Blackdome, 3985 [figure 6-7]

Blackdome, Thomas Cole, and Black Head are a part

of the same escarpment and are devoid of red spruce. This is

likely due to unique successional development of these

mountains that has resulted in the dominance of balsam fir

over red spruce, the dynamic of which is described in the

following sections.

There is evidence on Blackdome of periodic single-tree

mortality events, where a gap along the transect line in the

dominant balsam fir canopy is filled with mountain ash or

mountain maple saplings [figure 6-8]. However, seedlings of

balsam fir almost completely cover the mossy forest floor.

They have not yet reached a height that can be considered

6-6: The ground stratum on Hunter is healthy with typical

Catskill herbaceous species over moss stratification.

6-7: Blackhead Range, left to right, Thomas Cole,

Blackdome, Black Head.

6-8: Mountain ash with mountain maple seedlings


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established, but such a masting event will likely result in a

thick sapling layer similar to that on Hunter Mountain and can

tolerate the partial shade created by dispersed mountain ash.

Some small paper birches are present, taking advantage of the

thin soils. No paper birch seedlings or saplings were observed

that would indicate their eventually increase in frequency. The

forest floor is very lush, with moss mat over 3-4 inches deep covering most of the ground. Dominant

herbaceous species grow in great abundance with the balsam fir seedling mast [figure 6-9]. Overall, the

canopy was not closed, but it will likely become a closed canopy balsam fir stand if the seedlings are

established.

6d. Thomas Cole, 3943

The summit of Thomas Cole was dominated by a

healthy stand of mature balsam fir [figure 6-10]. Like

Blackdome, there was a field-like spread of balsam fir

seedlings. No seedlings or saplings of paper birch or mountain

ash were noted although there were dispersed medium size

occurrences. This further indicates their tendency as

opportunistic colonizers of an area, where a tree mortality and

canopy opening can result in the germination of their seed.

Scattered small hobblebushes were present in the understory.

These are young, and

have the potential to

spread rooting branches

to create a thick local

understory. Dominant

understory species

composition is similar

among the high summits, but Thomas Cole did

have a higher number of mountain woodferns

present. Thomas Coles understory community is unique; the moss layer has developed densely only on

6-9: The understory on Blackdome is extremely lush

with great species biodiversity.

6-10: Balsam fir stand on Thomas Cole, with

mountain woodferns beneath.

6-11, 6-12: Dense moss developing particularly on decaying wood

debris and not the ground. Note the ferns over moss-less ground.


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rotting stumps and wood debris, and not in thick ground mats like the rest of the sampled high elevation

forests. This could be a competitive dynamic with the also unique fern cover. Perhaps the ferns interact

with the humus in a way that hinders the development of a moss mat, restricting the moss to decaying

wood. [figures 6-11, 6-12].

6e. Black Head, 3942

Of the five mountaintops sampled, Black Heads

summit forest was the densest [figure 6-13]. This is

common among the mountains situated in higher elevation

zones where orographic precipitation collects over a central

point. Black Heads steep slopes dropping from its summit

to the Hudson valley floor, near sea level, are part of a

continuous mountain wall that makes up the eastern

Hudson Valley escarpment. The same ridge of mountains

that contains Hunter extends to this wall perpendicularly,

and the mountains positioned over the valley floor possess

extremely dense forests of balsam fir.

Balsam fir, which dominates Black Heads summit,

grows in great frequency. The first steep slopes from the

summit are a cover of balsam fir with an exceptionally thick

layer of moss seemingly pouring over the ledges [figure 6-

14]. When the fir grows in such a thick manner, the trees often

suppress each other and the overall rate of growth is slowed. Many of

the Catskill Mountains that receive greater orographic precipitation

share this variety of over story cover.On the opposite side, where the summit slopes away from the

escarpment wall, the forest is more open although the moss mat

remains just as thick. Many of the balsam fir along the sample here

had the top halves of their trunks snapped off by wind. In the

openings, young mountain ash, paper birch, and mountain maple were

6-13: Extremely thick growth on Black Head.

6-14: The slopes over the Hudson Valley receive

greater precipitation. Balsam fir grows at its thickest

and moss at its densest.

6-15: Mountain ash, mountain maple,and paper birch establishing a small,


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growing in greater frequency than openings on the other 4 samples, indicating that they might create

short-term small canopy dominance before the balsam fir saplings break suppression [figure 6-15].

6f. Main Analysis Results

The dominant over story trees are balsam fir and red spruce. In the highest elevations, balsam fir

dominates over red spruce in both frequency and basal area. On Hunter, the only stand sampled where red

spruce are present, the spruce were in decline and balsam fir is positioned to dominate in the future. This

does not indicate that red spruce throughout the Catskills is in decline, but that physiographic conditions

in the five highest elevations are more favorable to balsam fir than red spruce.

Paper birch, mountain ash, and mountain maple are present as opportunistic species, growing

where a canopy disturbance is evident. Mountain ash and Mountain maple do not create dominant

overstory stands in the Catskills and both are a sub-canopy species. However, if paper birch establishes

itself and is able to reproduce it may contribute to significant organic accumulation, furthering soil

development and expediting the migration of deeper-rooted hardwoods into the spruce-fir zone.

The understory stratum has overall higher biodiversity than the overstory. Dominant herbaceous

plants include mountain wood sorrel, clintons lily, sharp-leaved aster, starflower, and goldthread. These

tend to create small but very dense colonies, and their presence usually indicates stable, less disturbed

soil. A large array of mosses, lichens, and woodferns also make up the lush lower strata. Many rotting

pieces of tree debris lie on the ground, covered by a sheet of moss, lichen, and other herbaceous species.

The understory species are mostly small, less than 6 inches in height. Their development occurs on acidic

unfertile organic matter, mainly needles. Mosses are on elevated portions, such as logs or rocks. If higher

elevation hardwoods are able to establish themselves, like sugar maple or beech, the nature of leaf litter

changes, as will the conditions that understory species must be adapted to. Plants must have the ability to

grow above the taller layer of leaf litter, and the dominant understory species of the spruce-fir forests

would be replaced by taller, hardwood associated herbaceous species.

7. High Elevation Forest Community Dominant Species Biogeography

In this section the biogeography of each dominant species is discussed, including general growth

characteristics, morphological adaptations to available sunlight, soil depth, acidity and composition, seed

dispersal, and disturbance dynamics. Through these topics an understanding of the ecological niche and

seral stage each species inhabits will be established to further support the objective of this study. First

each species and forest stratification group and how they interact with their environment must be


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understood, then a comprehensive discussion is presented that defines and explains the high elevation

forest community as a whole.

7a. Trees

Balsam FirAbies balsamea [figure 7-1]- Balsam fir is distributed throughout Southeastern Canada and the

northeastern United States. In general, regions with cooler temperatures

with abundant moisture allow its growth, although it is tolerant of harsher

conditions. Annual precipitation during its growing season can vary from

6 to 25 inches and there can be between 80 to 180 frost-free days in the

year, with optimum growth occurring when there are 110 frost-free days

(Frank). This characterizes the balsam fir zones in the Catskill region,

where the areas balsam fir is distributed vary in annual precipitation

amounts.

Balsam fir is well adapted to the shallow glacial till soils atop the

Catskill mountains, as the most important determining factor for growth is

soil depth. It is able to survive in soils rich or poor in organics, but where

its stands are dominant the soils have a thick layer of mor humus and a

predominant gray A soil horizon (Frank). Nutrient leaching through abundant orographic precipitation,

the cooler temperatures, and the acidic coniferous litter layer contributes to the spodosol and inceptisol

soil formation. Cycling of organics and the maintenance of acidic spodosol conditions allow balsam fir to

uphold its dominance. It can tolerate a wide range of acidity, and once established it becomes a major

constituent of the forest cover.

Processes for reproduction and early growth of balsam fir allow it to become a dominant species

in the higher elevation Catskills wherever soils are shallow. Its sprawling coniferous growth shades out

deciduous seedlings and allows it to absorb all available canopy sunlight. The sunlight exposure then

triggers flowering in trees 20-30 years old. 83% of trees in a New Brunswick stand were able to flower

where balsam fir was dominant, 59% in a codominant stand, 6% in the intermediate layer, and none in a

suppressed layer (Frank). This shows the importance for balsam fir to establish itself as a dominant

canopy species wherever it grows in order to further reproduce and how it may become eliminated from

stands if shaded out by competition. Large seed crops are produced on 2 to 4 year intervals, and the

amount of time that seeds may be spread is long while the distances a seed may fall vary. September and

October are peak months for seed distribution and continues on through November. The flat, wind-prone

7-1: Medium sized balsam fir.


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Catskill summits allow seeds to be distributed over great distances, but the most effective distances are 80

to 200 feet. The seed embryos lay dormant, and the optimal location for development is in a mixed

stratified layer of moist organics and coarse textured minerals (Frank).

Soil moisture and temperature within a tolerable range

are the two most important factors for seedling development.

The dense moss layer, thick organics, and year round leaf

cover attributed with mature coniferous forests have a

compound effect to retain soil moisture in the Catskills,

helping the seedlings germinate and survive. Germination in a

mixed mineral-duff soil is more favorable, as a purely leaf

litter soil tends to desiccate faster and the heavy centralroot can extend through the humus. Drought, frost

heaving, and burial by organic litter contribute to

seedling morality before the seedlings can be

considered established. Once the seedling is about 6 inches tall it can be

considered established, and even more so if any branching has occurred

[figure 7-2]. After this point, the trees growth is influenced by the stands

unique competition. Hardwood sprouts, especially mountain maple in the

Catskills, are the main competition for a balsam fir seedling. Developing

balsam fir requires at least 50% full sunlight, and at that level deciduous

seedlings may also sprout in the same stand, bringing competition

(Frank).

The thin layer of organics atop mineral soil found in the Catskills

provides a good location for balsam fir root systems, which are most

commonly in the organic litter layer and the uppermost inches of the

mineral layer, provided there is satisfactory weathering to allow root

growth. Because the root systems are restricted to growing in such a

shallow and poorly developed area, older dense stands are especially

at risk to wind damage or kill after heavy rainfall and winds loosen

the root systems.

Depending on the sites physiography, a mature balsam fir is

7-2: This masting of seedlings can be consideredestablished. From here, intraspecific competition for

moisture, nutrients, space, and sunlight will occur, killing

off many of the future saplings, to the point where a few

young trees are left to possibly grow to maturity.

7-3: A mature, healthy balsam fir

just below the summit of Hunter.

7-4: This overly crowded stand on

Hunters summit has been stunted from

intraspecific competition.


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small to medium size ranging from 40 to 60 feet with diameters ranging from 12 to 18 inches. Balsam fir

has a tendency to become well established in the shade of larger trees, waiting for a canopy opening to

grow to its maximum. Some may reach 90 to 100 feet and 30 inches in diameter with a maximum age of

100-200 years, and the extent to which a balsam fir grows is very closely related to its unique site factors,

such as soil depth and mineral layer characteristics [figure 7-3, 7,4] (Frank).

Fire is a major damaging agent for balsam fir, but it is not a natural component of the Catskill

vegetational system and does not play a role in the development of balsam fir stands. Insects such as the

spruce budworm and balsam woolly adelgid are able to defoliate balsam fir and attack the stems, but have

not yet been introduced to the Catskills. Multiple species of

fungi cause decay within a living balsam fir, causing wood

rot by the time they are 70 years old. Currently the stands

of balsam fir in the Catskills are healthy. Instead of

introduced insects and fungi wiping out balsam fir, stands

are slowly being replaced as the soils become increasingly

thicker [figure 7-5]. The buildup of leaf litter allows

deciduous trees to become better established in the event of

a canopy opening. Balsam fir seedling are intolerant of

heavy leaf litter attributed with a deciduous stand, and

can then be eliminated as mountain paper birch,

mountain ash, mountain maple, black cherry, beech and

yellow birch become dominant species.

Red SprucePicea Rubens [figure 7-6]- The native range of red spruce

is in eastern North America, along the Appalachian Mountains

northward through northern New Jersey, central New York, New

England, and the maritime regions of southeastern Canada. Optimal

growth occurs in cool, moist climates with 36 to 52 inches of annual

precipitation, 100 to 140 days with snow cover, a maximum January

temperature of 20 to 30 F, a maximum July temperature of 70 to 80

F and 90 to 150 frost free days for its growing season (Blum, 1992).

The maximum development for red spruce occurs in higher elevations

in eastern North America mountain chains where there is more

7-5: Just below the summit of Sugarloaf Mountain,

mature paper birch and mountain ash are beginning to

gain supremacy. These balsam firs are still able to flower

as they are not yet in shade, but seedlings will havedifficulty germinating and establishing themselves in the

increased amount of organic matter.

7-6: Healthy, mature red spruce grow to their maximum on the

expansive summit of Plateau Mountain.


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humidity and rainfall is heavier during the growing season.

Like balsam fir, red spruce grows in mostly acidic soils comprised of spodosols and inceptisols. Its

wider distribution in the Catskills outside of higher elevations is attributed to its ability to grow on sites

unfavorable for many other tree species. A thin organic layer overlying unbroken rock on steep, sloped or

poorly drained valley bottoms with limited oxygen circulation limits the growth of many deciduous

species throughout the Catskills. Red spruce can often be found in such areas growing to its maximum

surrounded by saplings and seasonal streams [figure 7-7].

The maximum growth red spruce is 110 feet tall with a d.b.h of around 34 inches inches (Blum,

1992). Red spruce is able to grow close to that size on slope forests in the Catskills but atop to mountains

within the sample plots of this study it is a medium size tree at maturity, with a 12 to 24 inch d.b.h and 60

to 75 ft height. The strongest factor in determining growth rate is the sunlight condition; red spruce is able

to live in shade for many years but once it grows beyond the sapling stage it requires nearly full sunlight

(Blum, 1992).

Male and female flower buds will grow and open during May, located on the axil from the

previous years growth. Cone buds will separate by July, and mature between September and October to

grow 1.3 to 1.5 inches long. Once mature, the cones will be fully open for only a few days to receive

pollen. Every 3 to 8 years there will be a large seed crop with lighter crops between. Most seeds are

dispersed by wind and are germinated within 350 from the parent stands boundaries (Blum, 1992).

Following seed dispersal and deposition on a favorable seedbed, most of the seeds will germinate

next late may into early July with some germinating in the same autumn as dispersal. On desiccation

prone leaf litter, some seeds may lose their viability or delay germination into August. After one year it is

rare for a seed to remain viable (Blum, 1992). Like balsam fir, the main determining factor for

germination is adequate soil moisture, but unlike balsam fir, red spruce is able to germinate on almost any

soil medium. Mineral soils are the most favorable seedbed, while duff and humus are not as favorable

because they are more prone to heat and drying. Germination requires a light intensity of at least 10% full

sunlight but as the seedlings develop they require at least 50%, the same as balsam fir (Blum, 1992). The

seedlings are prone to the same damaging agents as balsam fir, including drought, frost heaving, and

crushing by hardwood leaf litter or snow. Red spruce seedlings and balsam fir seedlings are controlled by

the same factors but red spruce is much weaker and slower growing during its period of establishment.

While the parameters for germination allow a wide array of conditions, the reproduction ultimately

depends on seedling survival. The root system of red spruce seedlings is exceptionally slow growing for

trees and is very fibrous. This places a critical emphasis on the conditions of the top organic layers of the


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soil profile. Because the roots grow so slowly, if the duff layer exceeds two inches the seedling root may

not reach moist mineral soil to supply water during a dry period in its growth (Blum, 1992).

If the seedling manages to survive and grow to a height of 6 inches, it can be considered

established. It can meet competition from deciduous trees and brush once established, but it can survive

close to 150 years under suppression as a smaller to medium sized tree until it is finally released. It is also

the last of its associated tree species to begin height and radial growth in the spring and early summer

(Blum, 1992), and this may allow red spruce to grow in a pattern that is responsive to how earlier growing

trees have reached towards the canopy openings. Both spruce and fir are shallow-rooted, but red spruce

roots grow shallower than balsam fir. Red spruce is more susceptible to drought and requires a higher soil

moisture retention capacity. The bulk of feeding roots are located in the humus and in the top inch of

mineral soil.

Whether or not red spruce is more shade tolerant than balsam fir is an unsolved question (Blum,

1992), and the answer may lie in the varying soil conditions and climates that can better suit one species

over the other. The main competition for stand dominance is from balsam fir and other established

hardwoods that produce heavy shade like beech and maple. As soil depths increase, beech, maple and

other hardwoods are able to establish themselves in canopy openings. Beech and maple in particular

produce heavy shade and leaf litter, both of which are

detrimental to red spruce development. In the

Catskills, it is common for scattered, mature red

spruce to grow among a dominant overstory of yellow

birch and paper birch [figure 7-7]. As stated earlier

red spruce has the ability to live suppressed, but the

vigor of its recovery declines with age. In a stand

where this is dynamic takes place, balsam fir is able to

outgrow red spruce once the canopy opens. It will

take about 5 years before red spruce shows accelerated

growth once the opening occurs (Blum, 1992).

Like balsam fir, red spruce is especially prone

to fire damage but this is of little natural concern to the

Catskill Mountains, and forest fires are extremely rare.

Red spruce shares the same biotic damaging agents as balsam fir in the Catskills but has not yet been

ravaged by introduced insect populations. High elevation red spruce growth rates have declined

7-7: On the wetter middle slopes of Hunter Mountain,

~3,000, yellow birch is the dominant species. There are

multiple hollowed-out drainage routes for rain andsnowmelt from the summit, and red spruce takes

advantage of the abundant soil moisture in these small

coves. Its tolerances for optimal growth in high elevations

can be traced to where it is able to grow successful stands

in lower elevations.


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throughout the Appalachian mountain chain, and this is attributed to an interaction between insects,

diseases and the weakening by anthropogenic air pollutants. Studies have not yet indicated a significant

decline in Catskill stand growth rates, and the influences of anthropogenic pollutants are not yet

understood in the Catskill high elevation forests.

Mountain Paper BirchBetula cordifolia [figure 7-8]- Moist, moderately drained soils at higher elevations

and particularly north facing slopes provide a good habitat for paper

birch. It has a very wide native range across northern North America

wherever physiographic conditions favor its germination and

development, from northwestern Alaska, southeast to British Columbia,

and the northern Rocky Mountains states, and eastward through Canada

and the Great lakes region into New England extending south through

the Appalachian Mountains. It is essentially a northern species adapted

to cold climates, growing well in the harsher more exposed Catskill

summits, tolerating wide variations in precipitation from 12 inches

during the growing season in some areas in Alaska to 60 inches in

eastern mountains (Safford, 1992). Generally, a short cool summer and

a long cold winter during which snow covers the ground for a long

period of time is favorable for paper birch, and these climatic patterns are common to the Catskill

Mountains.

Because paper birch has ample genetic diversity and a very wide range, it is able to tolerate many

soil and topographic conditions. Deep well drained spodosols and inceptisols are the best sites for its

growth, which are common features of vegetational development on glacial deposits throughout its range

(Safford, 1992). In the Catskills, it is more abundant on drier sites with rocky slopes. It grows within a

mixture of other tree species within its forest cover type but because of its shade intolerance it grows in

openings and occupies positions in the upper canopy.

From the middle of April through early June a paper birch at least 15 years of age, optimally

between 40 and 70, can enter its flowering period (Rich, 1906). The seeds are matured from early August

until the middle of September and are then dispersed shortly after ripening. Some seeds may be dispersed

earlier as a result of birds feeding on the developing fruits. A good crop of seeds occurs every other year

and tends to vary in amount from one region to another. If a crown grows too many catkins, the seed

7-8: Paper birch and its unique bark.


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bearing fruit, the crown may deteriorate and foliage quality will decrease and growth will be stunted

(Safford, 1992).

Paper birch seeds are light and wing shaped, lending them to wind dispersal over great distances.

Despite the ability for far travel, most seeds fall under the stand in which they were produced (Safford,

1992). As a consequence of their small size paper birch seeds are extremely fragile. They are very

sensitive to moisture, temperature, light, and the soil medium of the seedbed. Mineral soil offers the best

site for germination, rates of germination on humus are reduced by 50%, and germination rates on

unbroken leaf litter are 10% of that in mineral soil, and twice as many seeds will germinate in a shaded

site than a full sun site (Safford, 1992). Although paper birch colonizes openings in the Catskill spruce/fir

forests, they do not germinate well in the full sun wind thrown openings. Instead, the established

seedlings can be found around overturned tree pits, mounds, and log micro sites where there is a shaded

dip and soil nutrients have been upturned and recycled (Kudish, 1971). Of these germinated seeds, those

located on humus will fare better than those germinated on leaf litter because of greater nutrient

availability. The heights of the seedlings after the first year of growth indicate paper birchs preference for

germination in disturbedpartially shaded areas, where taller growth was found in areas with 45% full

sunlight, rather than 100%, or even 25% or 13% (Safford, 1992).

Thin soils atop the Catskill Mountains allow paper birch to establish itself with its shallow root

system. Within the top 24 inches of soil most of the feeding roots can be found, and taproots do not form

(Kudish, 1979). If an extension of the root system grows to a diameter of the stem diameters, it will

become part of the permanent woody root system. Although the roots do not extend deep into the soil,

they do not contribute to wind damage. High wind will break the trunk of a paper birch more often than it

will uproot it, and these broken stems will generally sprout (Safford, 1992).

Young paper birch will grow rapidly, often reaching a diameter of 8 inches after 30 years. This

growth rate will decline with age, and at an older age its growth rate is insignificant. In a mature stand the

average d.b.h. will be 25 to 30 cm and 70 ft in height. Under optimal conditions a tree in an old growth

stand may exceed 76 cm d.b.h. and 100 feet in height. After 60 to 70 years the tree will mature, and few

will live over 200 years (Safford, 1992). Mortality rates are high within a paper birch stand. An individual

tree will express its role in the community by dispersing seeds early in its life, while older trees grow

slowly and do not reproduce as vigorously. If a tree is suppressed, it will shortly die unless released early

in its life.

During the late 1930s and 1940s, large portions of paper birch were killed off or severely damaged

all throughout its eastern range. From the crown back, the twigs and branches died or lost vigor,


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eventually killing off the entire tree during a period of 5 to 6 years (Safford, 1992). Shallow rooted trees

were most often damaged, and the root systems displayed symptoms before the crown. Many of these

trees sprouted new branches and eventually recovered, while the dieback subsided and is not considered a

current threat. The dieback may be attributed to acid deposition from fog. Although current populations in

the Catskills remain healthy, it is important to consider the possibility for unexpected ecological cascades

of degradation.

The forest floor is enriched with nutrients when paper birch leaf litter is in abundance. Calcium,

potassium, magnesium, phosphorus, and boron increase while manganese, aluminum, iron, and zinc

levels decrease. The nutrient enrichment can extend through thin organics to the top inch of mineral soil

where pH is also increased (Safford, 1992). Alteration of nutrient levels in soil previously occupied by a

coniferous forest with different nutrient parameters contributes to the decline and replacement of

spruce/fir stands (Kudish, 1971). The increases in nutrients, alkalinity and leaf litter contributes to the

process by which an increased number of hardwood species are able to colonize and establish themselves

in areas previously out of range, thus crowding out the spruce/fir stands.

Paper birch will either form a pure stand following a clearing by wind and ice in the Catskills or it

will establish itself in a mixture of varying extent within the spruce/fir community. More commonly it

will become an intimate feature of the Catskill spruce/fir forest, where it occupies openings in the canopy,

slowly altering the nutrient and organic composition of the forest

floor while burying conifer seedlings with its duff. Higher

elevation hardwoods, including beech, maple, yellow birch, and

black cherry are then able to establish themselves after a

considerable amount of time.

Mountain AshPyrus Americana [figure 7-9] American mountain

ashs native range occurs in northeastern North America, spanning

from Newfoundland and Nova Scotia south to New Jersey

and Pennsylvania. It appears in mountainous areas through

South Carolina and Georgia, and in the west it can be found

in Minnesota and eastern North/South Dakota where its

environmental parameters are met. It is a component of the

spruce-fir ecosystem as a member of the lower canopy, and

is codominant with balsam fir (Sullivan, 1992).

7-9: Young group of mountain ash.

7-10: Mountain ash branches grow spreading,


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Mountain ash grows as a shrub or small tree 10 to 30 feet tall with an average d.b.h. of 10-25 cm.

The trunk is slender and short with spreading trunks and branches, growing to a narrow rounded crown

[figure 7-10]. If it grows in a closed canopy system the trunk grow longer, splitting higher along the tree

to maximize sunlight exposure. The trunk, crown, and fibrous root system are very slow growing and

short lived (Sullivan, 1992).

Numerous birds eat the mountain ash berries, and this contributes to the main method of seed

dispersal. Flowering occurs from May through July, and the fruit ripens in August. The berries remain on

the tree throughout the winter. The distances seeds are dispersed are usually that of a few hundred feet

and germinate best in paper birch-spruce-fir cover (Sullivan, 1992). Rocky hillsides or thin soils atop the

Catskill Mountains provide the best habitat, and is very common in canopy openings. It grows well in

poorly developed shallow spodosols and inceptisols where the climate is cool, windy, and humid. These

features are common between Catskill summits and their tree constituents. If mature or semi mature trees

are scattered in a coniferous forest, mountain ash is able to establish itself well as codominant small tree.

Mountain ash is identified as a facultative seral species (Sullivan, 1992). It is shade intolerant, and

it is more abundant in early seral spruce-fir communities where a disturbance has set back succession and

less abundant in old growth spruce-fir communities. Along with mountain paper birch, mountain ash is a

factor in the transition from spruce-fir forest to a hardwood forest through canopy opening colonization

and deciduous duff accumulation.

Mountain MapleAcer spicatum [figure 7-11]- Mountain maples native range extends through

southeastern Canada and the northeastern United

States, and in mountainous areas throughout North

Carolina and eastern Tennessee. It is a member of the

spruce-fir ecosystem in commonly recognized plant

associations (Sullivan, 1992). It occupies a niche in the

understory sub canopy layer, scattered throughout the

mature sub-climax forests and will occasionally form a

dense shrub layer in a very disturbed forest. It grows

opportunistically where red spruce and balsam fir are

removed from the canopy layers.

Maximum height can be up to 33 feet and is

usually smaller, around 20 feet, with a maximum d.b.h

7-11: Multiple, mature mountain maples grow on the

slopes around Black Domes summit, with occasional

seedlings and saplings on the summit.


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of 15-20 cm. The trunk often grows short and crooked with a clumped bushy growth form. It grows a

shallow root system, with the majority of the roots located close to the soil surface. When the plant is

between 5 and 10 years of age it can reach maximum growth rates of about 1 foot per year, becoming

very slow growing once it reaches 40 to 50 years (Sullivan, 1992).

Through insect pollination the seeds are distributed by wind and require stratification throughout

the ground layer for best germination. In undisturbed soils where there has been no upturn or disturbance

the seeds will germinate at the highest rates. Once established, it can tolerate deep shade but grows best in

sun, using its bushy layered growth form to take advantage of periodic sunlight penetration through the

upper canopy (Sullivan, 1992).

In the spruce-fir community mountain maple grows in scattered groups in the understory sub-

climax community. It does not slowly invade as leaf litter accumulates; rather it is a feature of the

understory small tree or shrub layer. If it grows to a significant proportion it can suppress spruce or fir

seedlings, but ultimately it will give way to conifers, as it is short lived.

7b. Understory Shrub & Herbaceous Layer

Clintons Lily Clintonia borealis [figure 7-12]- Native to

North America, this perennial grows at a moderate rate

during the spring from older rhizomes. Although it is

characteristic of shady coniferous forests, it is full shade

intolerant. Clintons lily spreads extremely slowly, mostly

by vegetative clones through rhizomes. It can reproduce

through seeds via its small berries, but it takes up to 10

years for the perennial clone to establish itself to the

point where it can successfully produce seeds

(USDA/NRCS). The seedlings have low vigor and are

usually not successful in establishing a new clone

colony. At maturity, it will grow to a maximum height

of just over one foot. The long period of time required for a colony to establish dominance indicates its

sensitivity towards a site disturbance, such as upheaval of a nearby tree or smothering by fallen organic

debris during an ice or wind storm.

7-12: An established Clintons Lily colony. This species

is intolerant of soil disturbances, indicating that its

position on Hunter Mountain is stable. Hunter Mountain

has had patches cleared for construction in the past, but

the presence of this species shows that the larger forest

ecosystem is intact and healthy.


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Goldthread Coptis groenlandica [figure 7-13]-

Goldthread can be found throughout coniferous

forests of North America in cool, moist climates,

growing best in moderately drained spodosols

(Sullivan, 1992). It dominates the understory strata in

nutrient-poor areas or sites with abundant mor-humus,

characteristic of the micro site directly underneath

conifer trees. The damp, limited sunlight, mossy sites

where it can be observed atop the Catskill Mountains

are characteristic of its growing sites throughout its

entire range. Because of its preference for moist sites it is full sun intolerant, but it does require some sun.

Consequently, when a canopy disturbance occur,s it is intolerant of the new open conditions and is unable

to regrow (Sullivan, 1992).

Goldthread is an evergreen hemicryptophyte, growing from a creeping rhizome beneath the

surface as a perennial. It does not have a main stem, but rather grows layered branches very close to the

ground (Sullivan, 1992).

Mountain Wood Sorrel Oxalis Montana [figure 7-14] - Wood sorrel is a dominant understory species

throughout the eastern North American coniferous

mountain forests, primarily in spruce-fir forests. It

grows perennially in well-developed colonies comprised

of vegetative clones as geophytes, with its main point of

growth coming from beneath the ground (Pavek, 1992).

Because of its wide range and tolerance for an array of

site conditions, wood sorrel is not attributed with a

particular set of site characteristics. However, its habitat

in the Catskill Mountains is usually under a mature balsam

fir canopy. This implies a shady area with a thin organic

layer lacking a smothering annual leaf litter. The soil under

a pure balsam fir stand often has a lower water retention capacity, and this can affect the growing zones of

mountain wood sorrel that prefer mature balsam fir stands.

7-13: A very dense Goldthread colony in a moist, mossy site.

7-14: Wood sorrel grows close together but not in

dense clusters. Here it is seen on the moss layer,

indicating its preference for moister sites.


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StarflowerTrientalis borealis [figure 7-15]- Throughout eastern North America, starflowers may be

found in cool, moist, humus rich soils. It grows to a maximum

height of under one foot as a perennial and is most commonly

spread through seeds (USDA/NRCS). Its characteristic flower

consists of 7 white pedals, and colonies will spread to form a

mat on the forest floor. When observed in the Catskills it is

typically found growing out of dense moss mats. It is able to

grow in mixed high elevation forests where deciduous trees

contribute to the leaf litter and establish mature stands.

Starflower then has a higher tolerance for germination through

deeper leaf litter, but its primary habitat in the Catskill forest is in dense coniferous forests.

Hobblebush Viburnum lantonoides [figure 7-16]- Organic rich, moist forests in higher elevation

northeastern North America are the habitat for hobblebush. It

grows best in acidic soils with a mixed soil medium. Growing

up to 12 feet high, it tends to sprawl over wide distances by

growing pendulous outer branches (USDA/NRCS). These

branches may root once they make contact with the ground,

further establishing the colony. This tangle is a typical image

of the higher elevation Catskill forests where navigation in a

straight line becomes cumbersome, leading to its name. Fall

foliage is a brilliant red with fruits attracting birds.

7c. Mosses

A major characteristic of the high

elevation Catskill forest is a dense moss mat

7-15: Starflower grows mixed with other

species on the ground stratum.

7-16: Hobblebush creates thick spreads in the

forest. Its growth is associated the growth of

other high elevation understory species, and does

not inhibit their development.

7-17: The organic matter that this moss is growing from is

visible in the upper portion of this picture. Organic debris,

mainly pine needles, is visible, tangled underneath the moss

and scattered lichen. This eventually becomes part of the

humus, furthering the growth of this small area.


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covering the forest floor [figure 7-17]. These mats usually cover boulders, fallen logs, and grow up the

trunks of living trees [figure 7-18]. Upon close inspection, multiple species of moss grow over one

another and usually prefer one micro site. The life forms these different species will take serve a different

purpose that can be indicative of what kind of microenvironment it must contend with throughout its life

cycle. The growth forms ultimately serve a common purpose, which is water retention (Glime, 2010).

Reducing air exposure, thickening the boundary

layers vegetative thickness, and growing on top of

one another to protect each other can achieve the

water retention needed to sustain the moss mat.

Water retention and availability of moisture

is the primary determining factor in the distribution

of mosses. The boundaries for each species are

ultimately set by temperature, but growth within

that boundary is limited by availability of water.

The ecosystem where a moss mat grows is altered

through the retention of water (Glime, 2010). The

soil temperature under moss is reduced, which then

slows the rate of decomposition and nutrient cycling rate.

While nutrient cycling is slowed, mosses also tend to retain

nutrients absorbed from the soil within their younger tissue

for future use. Spruce-fir forests in the Catskills thrive

where there is a thick moss layer, and the slow growing

spruce roots are able to survive well under the moss. This

suggests that the nutrients that mosses retain are not in the

soil but are stored in a way that is available to feeding

roots (Glime, 2010).

Mosses play an important role in the Catskill

high elevation forest community. Spruce and fir

seedlings can often be observed growing directly from the moss mat [figure 7-19], benefiting from the

nutrient and water retention. Mosss tendency to store nutrients and transport those nutrients throughout

the living tissue depending on moisture availability indicates that their biomass is an important feature

when weighing the nutrient availability and fertility of the soil.

7-18: This lump of different moss species on a log collectively

retains moisture and builds organics. Wood sorrel is growing

from the organics that have accumulated. Moss contributes its

properties to help cycle, maintain, and grow the forest floor.

7-19: Balsam fir seedlings growing towards

establishment. Organics accumulated on the moss to the

point where the seeds could germinate, and now the

retained soil moisture and available, retained nutrients aid

the seedlings.


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7d. Lichens

Lichens are a symbiotic life form between fungal and algal

cells [figure 7-20]. They grow spreading colonies on bare

substrate or an organic surface such as tree bark or a log,

dissolving and drawing out nutrients and furthering the

chemical and physical weathering processes of mineral

layers [figure 7-21].

The distribution of lichen species and forms

throughout the Catskill forest depends on extreme

microclimate conditions that do not affect other species.

The texture of bark, temperature, moisture, acidity, and

availability of bare substrate are factors that determine

what sites are best suited for a specific variety of lichen

(Larson, 1980).

These life forms developed in response to the micro

site and what kind of substrate the lichen is feeding from.

The internal morphology however, is consistently similar

across all species, where the bulk of the tissue is a fungal

component of the lichen colony [figure 7-22] (Waggoner). The

cortex is where the lichen colony comes in direct contact with

the outside environment. Here, the filaments are packed tightly

to keep other organisms and to minimize the inner filaments

direct exposure to sunlight, which will damage algal cells.

Below the cortex the fungal filaments lose their

density. The algal partner cells are then able to

live and distribute themselves just below the

cortex in the symbiont layer, in an arrangement similar to leaf cells in order to maximize photosynthetic

production. Below that algal layer is the medulla layer, where fungal filaments are tightly woven and

attached to the underlying substrate. Enzymes are emitted to break down the substrate, or if the lichen is

growing on organic matter it is using the host as a bed for photosynthesis.

7-20: Various species and growth forms of lichen

growing atop a sandstone cliff on Hunter Mountain.

7-21: The dark, loosely attached lichen shown here is

not the only lichen in this picture. The discoloration

on this rock is actually complete lichen cover.Enzymes are released that slowly chemically erode

the rock, contributing to the breakdown process of

the Catskills.

7-22: Internal lichen morphology. Source: Waggoner, B. with

Berkeley University.


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In boreal ecosystems, which include the coniferous forests of the high elevation Catskills, lichen is

an important factor in nutrient and biomass accumulation. Metabolism in lichen is opportunistic, and

whine moist climatic conditions are favorable lichen will absorb water, becoming dense and sponge like,

carrying out its metabolic processes for as long as possible and returning to a state of inactivity (Larson,

1980).

7e. Ferns

The dominant variety of fern found

throughout the high elevation Catskill forest is

mountain wood fern. They reproduce both by

spores and vegetative cloning through growing

male, female, and bisexual plants. Spores may be

dispersed by wind collect in great quantity in an

area where ferns are absent, colonizing a new area.

Vegetative reproduction through rhizomes is more

common, showing the importance for a colony to

become well established before it is able to spread

(USDA/NRCS). Mountain woodferns grow in a

very wide variety of physiographic sites, but in the

Catskill Mountains they are commonly found in

cool moist woodlands, both in shade and sun. They

thrive in the acidic, shallow, rocky, organic rich soils found throughout the mountains, with a strong

affinity for moist sites. Studies throughout the range of woodferns have mixed conclusions as to what

triggers their spread and eventual understory dominance in a mature forest (USDA/NRCS). In the Catskill

Mountains, mountain wood fern grows as a member of the mature forest community. There are many

areas known as fern glades, where wooderns grow to their maximum and cover dense patches of the

forest floor [figure 7-23] (Kudish, 1971). The presence of ferns does not indicate a disturbance or seral

stage. Instead, they are a very well developed fern colony that has out competed other members of the

understory strata, and have colonized the area independently of a facultative disturbance event.

7-23: Dense understory of fern under mature balsam fir

growth, on the first slopes below the summit of Thomas Cole

Mountain. The codominant understory species in this stand is

Clintons Lily, which is intolerant of site disturbances.

Because of the presence of a disturbance-intolerant species and

mature climax community tree species, it can be concluded

that this site is in its mature form. While mountain woodfern

was sparse in the high elevation samples besides Thomas

Cole, it is a component of the mature high elevation Catskill

forest.


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8. Catskill High Elevation Forest Community Discussion

The high elevation Catskill forest is an ecosystem undergoing successional progression during the

present post-glacial period. The sedimentary bedrock, exceptionally weathered and carved during

complex periods of glaciations, has been broken down into mineral soil through physical and chemical

erosion. Derived nutrients fixed by early successional species and the decayed biomass have been cycled

to create the organics comprising the soil. This process began once glaciers retreated, and the few alpine

glaciers remaining kept the upper reaches of mountainous regions out of reach to the pioneer species

struggling to establish the new forest.

The process of an organic layer being thickened over continuously weathering mineral soil and

bedrock is ongoing, present as the high elevation spruce-fir and balsam fir forest assemblage of the

greater Catskill forest ecosystem. While many lower elevation shelved escarpments share the same

characteristic thin organic layer and bedrock weathering, these are topographical features within bounds

of the hardwood forest community. Slide, Hunter, and the Blackhead Range are the upper reaches for the

forest migration upwards. The forest analyzed on the five highest individual mountain elevations of the

Catskill Mountains is a representation of the biodiversity that is produced and adapted to the physical

limitations on survival currently present. It also provides insight into the dynamic forest succession of the

region. While it is true that the mature conifer forest is the climax community for its set of physical

limitations, the accumulation of organic matter alters the duff and soil composition to the point where

different tree communities have a chance to contend with the conifers.

Because the dominant tree species are balsam fir and red spruce in the region of this studys scope,

the forest is ecologically defined as a red spruce- balsam fir forest. The ecological definition for the region

of balsam fir forest is not appropriate. Even though Slide and other mountains are completely dominated

by balsam fir they are still a spruce-fir ecosystem. This is because the domination by balsam fir over red

spruce is a part of their seral dynamic. There are Canadian boreal forests dominated by balsam fir that are

a unique ecosystem apart from spruce, but in the Catskill mountains it is possible, through a set of

disturbances and seed dispersions, for conifer stands of either balsam fir or red spruce to be completely

replaced by one another. Several documentations by 19th century naturalists and early surveyor remarks of

the Catskill Mountains mention forest communities in local regions that are not present today (McIntosh,

1964). This shows how the forest is changing with every tree generation that becomes established under a

certain set of ecological circumstances that are altered as disturbances and organic accumulations

progress.


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The field study conducted provides an insight into how this process is undergoing and what

environmental processes are at work behind the evolving forest succession. The over story red spruce-

balsam fir canopy is the catalyst and determining factor for the vegetational processes in the middle and

understory. Shade and the organics deposited by tree biomass sustain a large part of the environment

needed to secure the habitat for herbaceous and ground story vegetation. The two primary canopy trees,

balsam fir and red spruce, are in competition with one another for stand dominance. Where mature red

spruce dominates, it has taken advantage of a canopy opening after possibly having been suppressed by

shade or lack of space. Its fast growth once it achieved full sun enabled it to out grow and shade the

balsam fir around it, which will then not be able to enter its reproductive flowering stage.

Conversely, where mature balsam fir dominates a stand which is the case on Slide Mountain, the

balsam fir has been able to take advantage of the harsh environment that red spruce has failed to well

establish itself in. Balsam fir grows faster, and its roots grow deeper than red spruce. Deeper root growth

allows balsam fir to reach the top layer of mineral soil and spread farther than red spruce to find soil

moisture, and it is also able to tolerate much drier soil conditions than red spruce. Slide mountain was the

most recent to be exposed during deglaciation, and its thin soils provide a condition where balsam fir is

the only tree species present on the highest elevation. Mountain ash, mountain maple, paper birch, and

occasional lower elevation yellow birch grow along its slopes, and as the organic layer accumulates these

may migrate higher. Slide is also recovering from human disturbance on its highest elevation, but this

disturbance does not appear to have eliminated other tree species or have had a major alteration in forest

succession.

Disturbances will occur and the domination of one species over the other is temporary, as is the

pr

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