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Trees Along the Crest of the Niagara
River Gorge from Devil's Hole to DeVeaux (Whirlpool)
Steps in New York State P. M. Eckel |
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Trees Along the Crest of the Niagara
River Gorge from Devil's Hole to DeVeaux (Whirlpool)
Steps in New York State by P. M. Eckel
Controversy
exists today regarding the fate of the natural resources along the crest of
the Niagara River gorge. The gorge is a seven-mile feature shared by two
countries, the United States (eastern rim) and Canada (western rim) of this
north-south trending geological feature. Government and quasi-government parks
agencies and a power authority (New York State) own and/or manage the
landscape along the gorge, not always in keeping with public views as to
management goals or mandates. One major
public-private initiative is the fate of the Robert Moses Parkway, a paved
road running close to and parallel to the crest of the eastern rim of the
gorge. Local ownership of this highway is apparently by the power authority
(except for those portions, including the actual roadbed, that are owned by
Office of State Parks, Recreation and Historic Preservation), but it is
maintained by the New York State Department of Transportation. Currently
there is a public movement to remove this parkway. As it parallels Lewiston
Road, it can be considered to be redundant. This is not the case with the
Niagara Parkway on the Canadian side that parallels the crest, and for which
removal is impossible due to adjacent residential development.
The Parkway
begins upstream at the North Grand Island Bridge, follows westward along the
upper Niagara River to the cataracts in the city of Niagara Falls where the
Niagara Reservation, a State Park, is located. The road turns north here at
the southern terminus of the gorge, leaves the Reservation, continues along
the River, following its high bank (the gorge rim) along land in part
apparently owned by NYPA with interruptions associated with the international
bridges, other State Parks, and the State Parks maintenance garage. Downstream,
the roadway bisects two State Parks (DeVeaux State Park and Whirlpool State
Park) in the vicinity of the whirlpool at the base of the gorge, which is a
feature of the Niagara River. There is another State Park, Devil's Hole State
Park to the north, the power generating facility of the New York Power
Authority (NYPA) at the northern boundary of this, the gorge terminating to
the north at Lewiston, New York, at a State Park: Artpark, owned by NYPA but
with a layer of management by New York State Parks. The single
consistent public mandate for all the agencies is the preservation,
protection and restoration of the native ecosystems along the gorge, along
its top and down at the river's edge. The present initiative to remove the Robert
Moses Parkway, primarily along the crest of the gorge, is within the public
interest in correcting what is considered to be an error, and to restore that
landscape to its natural condition. To help
give more precision to the exact condition that is desired in this respect,
this author thought it expedient to investigate the natural botanical
character of the present crest vegetation, primarily its trees, as trees are
the primary natural control of the ecosystem that develops within and beneath
the canopy. To begin
this assessment, a field excursion on a single day, September 23, 2004, a
bright, sunny day, was taken along the gorge crest from Devil's Hole State
Park in the north, towards the south, or upstream, to the stone stairs just
north of Whirlpool State Park, a distance of about one mile. In future
papers, other sectors of the gorge rim will be discussed. Description of the Niagara River Gorge
Crest The gorge
of the Niagara River, part of the border between New York State and the
Province of Ontario, trends in a north-south direction in the section between
the Whirlpool (DeVeaux) stone stairs from gorge crest to shoreline on the
upstream end (south) to the stone steps at Devil's Hole at the downstream end
(north). The eastern, or New York State, shore of the river faces west and
receives the brunt of the prevailing westerly winds as well as the afternoon
sun. This condition tends to make the crest (historically known as the
"High Bank" or gorge rim or crest, as opposed to the "Low
Bank" or shoreline at the base of the gorge), generally arid. The low
bank is in shade generally until noontime during the autumn. The sunlight
exposure on the high bank intensifies during daylight hours in all seasons,
and receives pressure toward aridity due to evaporation pressure from winds
coming out of the west. This aridity is intensified because of soil depths
varying from none (in alvar situations where the dolomitic bedrock is exposed
at the extreme rim) to thin soil to soil of some depth in ancient river deposits.
This soil absence or deposition is, in undisturbed areas, a function of the
history of the river. When the
cataracts were situated at the extreme north end of the present seven-mile
gorge, at the axis between the towns of Queenston, Ontario, and Lewiston, New
York, on opposite sides of the Niagara River, the actual shoreline of the
river was approximately 250 feet in elevation above the level of the plain of
the ancestral Lake Ontario, when its waters lapped against the foot of the
north-facing, east-west trending Niagara Escarpment. The gorge is an
invagination of this continuous escarpment. As a shoreline, the soils of what
is now the crest were composed of river sediments with a mixture of erosion
byproducts as terrestrial soils and bedrock interacted with the forces of the
river water. Ancient shells and other biological debris characteristic of
this habitat in the "upper bank" may still be exhumed from the
soils along the crest. Soil depth varies as the curves in the river sometimes
drew the force of the water against the bank, when erosion and scouring would
occur, and times when the force of the water was directed away from the bank,
when deposition occurred. Variation would also derive from the breadth and
depth of the river channel, water flowing faster when the channel narrowed
and slower as it broadened out. Each time
the brink of the southward-eroding cataracts collapsed through various
erosive pressures, as for example, the acidic waters dissolved ever widening
chinks in the angular lines of breakage in the dolomite caprock, coupled with
the forces of hydrostatic pressure (all still active at the brinks of the
cataracts as they occur today seven miles south of Lewiston-Queenston), the
banks of the river downstream of the brink became abandoned, leaving them
"high and dry." The Ancestral Crest Forest The
general impression is that the forest in this section of the gorge crest is a
dry mixed Oak-Hickory woodland. The dominant trees are Red Oak (Quercus rubra), White Oak (Quercus alba) and Pignut Hickory (Carya glabra-ovalis). Subdominants
include primarily Hop-hornbeam (Ostrya
virginiana), White Ash (Fraxinus
americana), and Basswood (Tilia
americana), with a little Sugar Maple (Acer saccharum), Black Cherry (Prunus serotina), Tulip Tree (Liriodendron
tulipifera), rarely Black Oak (Quercus
velutina) and Shagbark Hickory (Carya
ovata), although I am guessing that at an earlier time there was more of
this last tree species. I would suggest, after consultation with Ecological Communities
of New York State (Reschke 1990) that overall this forest type conforms to
the Appalachian Oak-Hickory Forest community in the Forested Uplands section
of that booklet. It is a general woodland community that seems to occur
"throughout upstate New York north of the Coastal Lowlands ecozone; most
common south of the Adirondacks ecozone" (p. 55). Although
this seems to be the general community type in this section of the crest,
there are exceptions, such as the presence of a Chestnut Oak (Quercus muhlenbergii) community in the
southern section of Whirlpool State Park,with a match across the river in
Ontario on Wintergreen Flats. Another variation occurs where soils are deeper
and Sugar Maple (Acer saccharum)
becomes more numerous. Note also
that an entirely different forest type exists perched within fissures and
cracks in the dolomitic caprock of the gorge out of sight and out of mind,
and that is the forest of Arbor Vitae or Eastern White Cedar (Thuja occidentalis L.) Although occasionally this
evergreen tree is seen along the crest, in this section none were noted.
Their presence is screened by the shrubs and trees just outside of the
path-fence.
Looking
north, there are three habitats, the crest vegetation on the left beyond the fence
where most of the native species diversity occurs, the central wooded area
with canopy with the shrub and herbaceous layers absent due to maintenance by
the State as a lawn. On the right is the Parkway and blue sky (canopy absent)
with no shaded buffer. The tall grasses and forbs on the right hand slope are
there because of a recent decision by the parks administration to not mow.
For what purpose this policy is in effect remains to be seen. Most species
growing up are weeds. In the foreground is a stump indicating eventual forest
morbidity as present trees age and are not permitted to regenerate nor are
they to be replaced by genetically identical offspring. Present Conditions: The Crest Tour from North to South The area
studied is a narrow woodland strip (variably perhaps 30 to 100 or more feet
wide) about one mile in length contained between the western boundary of the
asphalted Robert Moses Parkway and the crest of the Niagara River gorge. On
the crest-side of this strip a pedestrian path and a metal fence occur, the
fence creating a barrier between the path and a special forest community in
the narrow strip of land between the fence and the drop-off on the gorge rim.
There is
no buffer where the wooded tract abuts the Parkway, with lower growing
plants, such as shrubs or small trees, to protect the woodland soils from the
open, exposed Parkway. A forest buffering structure may be seen in the
species composition in the extremely narrow strip (perhaps on average less
than 10 feet wide) between the fence separating the path from the open crest
of the gorge. Such a habitat, protected by the fence, gives some indication
of what the crest habitat might have looked like, especially since the
woodland under study here is itself an edge, but an edge to the original
woods in a more regional context that once occurred east of the Parkway in
the urban areas adjacent to the gorge in the City of Niagara Falls.
Looking
north from the south boundary of Devil's Hole State Park one can see the
unnaturally flat lawn area and how vulnerable to deterioration of the natural
experience paving this path would be. Such paving would clutter an already
over-modified environment and encourage guttering parallel to the pavement
edges, encouraging erosion and the introduction of more weedy species. As at
Whirlpool State Park, the habitat is somewhat disturbed. The canopy, as at
Whirlpool State Park across from DeVeaux College woods, is essentially
intact, casting a dappled shade. The habitat also has lost its shrub layer
except on the far side of the crest fence where a variety of native and weedy
shrubs occur. The woodland is relatively clean of introduced species (except
invasive shrubs, as discussed below). The European Bird Cherry (Prunus avium L.), seen in so many
Niagara woodlands, is absent here except for one old tree in more open
ground. At this time of year (September), the herbaceous layer is composed of
various Aster species and predominately the Zig-zag Goldenrod (Solidago flexicaulis L.) with a little
Blue-stemmed Goldenrod (Solidago caesia
L.) and rather tired Early Goldenrod (Solidago
juncea Ait.), because, as the earliest of the Goldenrods to flower (as
early as July), it is well into seedset by late September. Among the
Asters, the most striking and common is Arrow-leaved Aster (Aster sagittifolius) with white
flowers in full sun, turning somewhat blueish in the shade and as the flowers
mature. There was surprisingly little Tall White Aster (Aster simplex Willd.), perhaps because this species is more
characteristic of meadows in full sun. Everywhere
the ground was covered with thin-stemmed grasses of the genus Poa,
predominantly Kentucky Blue-grass (Poa
pratensis L.) with mixture of Poa
nemoralis L. Toward the crest there occurs the Canada Blue-grass (Poa compressa L.) which, despite its
common name (Canada Bluegrass), is a European, for instance, species that has
subsequently invaded the Niagara grasslands, probably at a very early date.
These grasses are not typical of the original soil cover, as in what may be
the only example of untouched crest vegetation I have seen to date (report in
progress). The grasses are so dense that little bryophyte cover exists on the
soils, another change from the original condition where the canopy was more
closed, perhaps with the addition of a shrub layer. Our native Poa species
generally have no rhizomes: Poa
compressa and Poa pratensis both
do, hence their extensive mat-forming colonial presence throughout the
Niagara woodlands. Upon
leaving the parking area near Lewiston Road at Devil's Hole and approaching
the pedestrian overpass over the Robert Moses Parkway, several very mature
trees occur: Red Oak (Quercus rubra L.),
two Hickory trees with essentially smooth (i.e. hairless) leaves (Carya glabra (Mill.) Sweet, the Pignut
Hickory), a large and beautiful, but decidedly horticultural Ginkgo tree (Ginkgoa biloba L.), two other Hickory
trees with shaggy bark (Shagbark Hickory, Carya
ovata (Mill.) K. Koch), two Tulip trees (Liriodendron tulipifera L.), more Red Oak, and Black Locust trees
(Robinia pseudoacacia L.).
White
Oak leaves On the
urban-side overpass abutment there was a Siberian Elm (Ulmus pumila L.), an alien species of street tree. On the gorge
side of the overpass there was a Norway Maple planted (Acer platanoides L.), the standard regional street tree, as well
as two very large, very old Hawthorns that the New York parks administrations
have used to plant in such areas, but which is alien to the region, occurring
naturally south of our area: the Washington Thorn (Crataegus phaenopyrum Medic.).
This shrub has been planted also at Devil's Hole in the abandoned northern
crest sectors of the park, at Whirlpool State Park, Goat Island and other
areas. Immediately
an American Basswood tree (Tilia
Americana L.) presented itself on the gorge-side of the path fence. This
and other native species occur on both sides of this fence, creating a canopy
that extends from the Parkway on the left (facing south) to the fence and
gorge crest on one's right. The Hop-hornbeam (Ostrya virginiana (Mill.) K. Koch) is a subdominant whose
frequency rises and falls in swarms along the path, as with the dominant
trees. Here there
are the amazingly plentiful of the Hickory species Pignut and Small-fruited
Hickory (Carya glabra (Mill.) Sweet
and Carya ovalis (Wang.) Sarg.)
with these medium to huge-sized compound leaves. Remains of their nuts litter
the ground. There is more Hop-hornbeam (whose leaves resemble Birch because
it is a member of the same family: Betulaceae). As
flowering herbs appear, the Goldenrods already mentioned, at least three
species, various Asters, White Snakeroot (Eupatorium
rugosum Houtt., there is one Shagbark Hickory on the crest, the tired
remnant of a spring wildflower population of False Solomon's Seal (Smilacina racemosa (L.) Desf.). There is
no getting around the sad thickets of Buckthorn (Rhamnus cathartica L.) that crowd the crest along the fence in
their tedious monoculture. This is the number one enemy of natural or passive
regeneration schemes, the number one invasive species in both natural and
disturbed areas. Anywhere and everywhere this shrub should be eradicated. One
escaped shrub of the alien English Hawthorn (Crataegus monogyna Jacq.) was seen. In
light-wells where the canopy has been broken by tree removal or tree-fall,
weeds flourish: the weedy Poas, the
Bluegrasses already mentioned, and the Orchard Grass (Dactylis glomerata L.) that flourishes in the unmown open areas
in the south sector of Whirlpool State Park, where individual culms can rise
as high as five feet in dense lawns with other weedy species. Note the
proliferation of these plants along the Parkway where the canopy ends. A very
small number of Sugar Maples (Acer
saccharum Marsh.), only seven inches diameter at breast height, are
encountered, which is unusual as most of the native forest in the region has
been characterized as Beech-Maple dominated. Here along the crest it appears
to be Oak-Hickory, as discussed above. A Black
Cherry (Prunus serotina Ehrh.)
crops up here and there all the way to Whirlpool State Park upstream, to the
south. A small amount of weedy Honeysuckle occurs across the fence (Lonicera sp. either L. tartarica L. or L. morrowii Gray). More
Pignut and Small-fruited Hickory with festoons of River Grape (Vitis riparia Michx.) occur, the Red
Oak becomes more conspicuous. Further on is another vine, one of the two
species of Virginia Creeper in our area, and, some say, the only native one, Parthenocissus vitacea (Knerr) Hitchc.
A large Norway Maple occurs on the crest, which should be removed, then
another. Six Hop-hornbeams line up in a row, then six Black Locusts (Robinia pseudoacacia), which should be
replaced with native trees. Black
Walnut (Juglans nigra L.) is very
infrequent, probably because it has a rather opportunistic capacity to
establish itself on ridge tops and the tops of talus slopes, whereas here
there is a fully mature canopy on flat land. Two White
Oaks (Quercus alba L.) appear.
Their numbers increase until they replace the Red Oak in places. On the
crest the round, smooth leaves of a native species of Juneberry or Shadbush (Amelanchier sp.) appear, a small tree.
These trees hide in their summer-autumn somberness their earlier beauty as
they shoot their whitened canopies open in early spring along the gorge crest
and talus forest on both sides of the river. A modest
population of spring wildflowers can be seen now, among the Goldenrods and
Asters, and here there is an Early Meadow-rue (Thalictrum dioicum L.), part of the original crest woods
herbaceous flora. A single
large trunk of the alien tree, the Little-leaved Linden (Tilia cordata Mill.) grows on the crest. Noteworthy are three
populations of Witch Hazel (Hamamelis
virginiana L.) growing beyond the fence. It is nice to see this native
shrub upstream because the only populations I am familiar with occur in the
downstream woods section of DeVeaux College woods. It is a species that
should be part of a restoration of the shrub layer under these trees in
similar native species assemblages as at DeVeaux. Another
native species seen here was the Red-osier Dogwood (Cornus stononifera Michx.). More Shadbush appeared, but then
disappointingly, more Black Locust. Near the
parkway margin one Honey Locust (Gleditsia
triacanthos L.) could be seen. This is another inappropriately planted
replacement tree that should be removed as it is capable of spreading in the
wild. More White
Oaks of great size appear as the walk progresses southward, a large grove
opening up as the path swings out into the cavity of the gorge, creating a
wider space between the Parkway and the crest. Here there are more numerous
native wildflowers, particularly the Arrow-leaved Aster and the Smooth Aster
(Aster laevis L.), the only plant
seen on this day. There is a Black Walnut tree and chipmunks, then Basswood.
Species of fungus spring from the ground. Here the
White Ash (Fraxinus americana L.)
appears. Its numbers will increase as one continues to walk upstream. The
forest continues from this grove in a mix of Basswood, Hop-hornbeam, Red Oak,
and White Ash. Two single stems of the spring-blooming Smooth Rock Cress (Arabis laevigata (Muhl.) Poir.) can be
seen in fruit, clinging to the bases of White Oak trees. This is the only
habitat in which they can exist as long as the mowing continues that destroys
their ability to establish themselves. The native
shrub Round-leaved Dogwood (Cornus
rugosa Lam.) can now be met in the woods beyond the fence, separating the
path from the gorge, a striking shrub in its genus, found, together with the
Pagoda Dogwood (Cornus alternifolia L.f.),
on the talus slopes below. A few stems of the Bottle-brush Grass (Hysterix patula Moench) grow on the
crest. Just
beyond the stone bridge over the dried up stream channel, at the only station
where Garlic Mustard was seen to have become established, the Paper Birch (Betula papyrifera Marsh.) appears and
will continue to be a woods component as one continues upstream to Whirlpool
State Park. This is an early colonizer in the disturbed talus slopes below
and in newly exposed habitat along the river's edge. This walk
along the crest ends with a rather steep slope down to the head of the stone
stairs (DeVeaux or Whirlpool Steps) leading down to the river's edge. This
declivity is dense with vegetation both weedy and native, with Slippery Elm (Ulmus rubra Muhl.), White Ash,
Buckthorn, Basswood, Paper Birch, Bird Cherry, Garlic Mustard, Dandelion (Taraxacum officinale), Buttercup (Ranunculus acris), and Deadly
Nightshade (Solanum dulcamara).
This area would be a good candidate for removing periodically the alien
species and leaving the native ones. This area has been highly modified and
disturbed, and is a good candidate for restoration work.
View
looking upstream (south) toward the Whirlpool and Ontario, Canada. This
section of the gorge has stunning views from the pathside. A comparison with
the gorge rim walk on the Canadian side for visual grandeur might be
instructive. Discussion Note should
be taken that there were no coniferous species observed in the tree component
in this strip of woodland. Old images and photographs, however, show that
such trees once occurred along the rim. The two species that are absent today
are the White Pine (Pinus strobes L.),
which was most likely a crest species, and Hemlock (Tsuga canadensis (L.) Carr. which would require a more moist,
protected station, and which trees do occur on the moist, cool talus with its
deeper soils below the crest. Such trees were eliminated from this area
during the height of the lumber and leather industries in the Tonawandas and
elsewhere locally in the early decades of the twentieth century. The tannins
in Hemlock were particularly valuable. It is
possible that the complete absence of White Pine may have been due to the
White Pine Blister Rust, caused by Cronartium ribicola
(Uredinales: Cronartiaceae), a rust fungus presumed to be native to Asia and
brought into the United States from Europe at the end of the Nineteenth
Century. The alternate host to White Pine is a plant from the genus Ribes, our Gooseberries or Currants.
The Niagara Gorge flora has numerous species and individuals of this genus
throughout, but it seems to be mostly the European Black Currant that is considered
to be the alternate host. One of the
most striking co-dominant trees along the crest is a species of Hickory. It
is a curious species in that group, genus Carya,
because people are still debating whether specimens of it belong to one or
two species groups: Carya glabra,
with C. ovalis as a synonym, or Carya glabra as distinct from Carya ovalis. Botanists who insist
that these are two distinct species instead of one variable one, will enjoy
selecting one species or the other out of the relatively large population of
this tree along the crest. Most of the trees have five leaflets, but several
occur with seven, and the leaflets of these latter are very large, compared
to the 5-leafleted type. All the leaflets of these trees are conspicuously
free of hairs. All the other species of Hickory in the area are very hairy,
especially on the underside of the leaves. The crest hickories have a
pleasing freedom from hairs that makes them cool to the touch on a hot
September day. Some of the trees have leaves with hairy rhachises, some
smooth. In all cases there are scattered dark brown glandular dots on the
underside of the leaves near the corners of the little veinlet areas
(areolae), and often pubescence underneath in the vein angles. Seven leaflets
correlates with C. ovalis, as does
a general shagginess or peeling quality to the bark. Some leaves of this type
have very few of the glandular dots characteristic of both tree forms. There
are many trees with smooth bark (the C.
glabra form), and plenty with sort-of shaggy, sort-of smooth bark, in
other words, such variability that it is likely to be one variable species
after all. The
definitive character has to do with the fruit: those of Carya ovalis (Wang.) Sarg. in late fall when the fruits are fully
mature, the husks split apart all the way from the tip to the base. In Carya glabra (Miller) Sweet, the husks
split only halfway down the fruit. This leaves the observer wondering, when
viewing a half-split husk whether the fruit was interrupted from splitting
all the way or not. Perhaps it
is best to see these as one species, and so they are treated here. The stand
of these kinds of hickories along the crest is a wonderful scientific
laboratory to study this interesting problem in plant taxonomy and would prove an interesting learning
challenge to student groups as well as individuals. Who knows, but a case
could be made that these trees represent two distinct species that can be
distinguished satisfactorily from one another in this particular locality. There are
only two other Hickory species that I have so far found along the gorge
crest, and these are first Carya ovata (Miller)
K. Koch, the Shagbark Hickory, conspicuous for its hairy leaves and
leaf-rhachis, with a lingering, rather dense tuft of hairs near the apex of
each tooth on the leaflet, and its thicker husk (3-10 mm whereas those of Carya glabra 0.6-2 mm thick). The nuts
of Carya ovata are larger, too (2.1-4.1 cm long, but only 1.6-3.2 cm
in Carya glabra). The overlap in measures is clear, but still, the Carya
glabra along the crest has overall smaller nuts than the relatively
fewer trees of Carya ovata (these at Whirlpool State Park with several
large trees by the Main Street (Lewiston Road) parking area at Devil's Hole
beside the path leading to the parkway overpass, Main Street side). One tree
of Carya ovata was noted along the crest. The
second, even less common Hickory is Carya cordiformis (Wang.) K. Koch,
the Bitternut Hickory, with very hairy leaves and fruits with prominent
wing-like ridges along the sutures. These trees never have leaves with five
leaflets (always 7-9 generally narrow leaflets). The most definitive
character of this tree is the bright orange, long, skinny bud at the ends of
the twigs (those of all other hickories are dark brown to nearly black). This
bud is so distinctive that some taxonomists are inclined to set this species
apart in its own category. Among the
Hickories, other than numerous trees of Carya glabra, only three trees
of Carya ovata were seen on this
walk between Devil's Hole and DeVeaux Steps on this particular day (September
23, 2004). People Using the Parkway and the
Forested Path. Equally
numerous groups were seen to utilize both the closed-off Robert Moses Parkway
lanes and the forested path along the fence nearer to the gorge crest. This
was during a workday, but there was a surprising number and diversity of
pedestrians, both male and female, young and old, singles, couples and in
groups. People employing strollers with infants, of course, used the paved Parkway.
Parkway users were exposed to the full September sun, whereas there was a
constant cooling shade along the path. Oddly
enough, it was the joggers who enjoyed the uneven path and shade, although
the newly paved Parkway lanes were conspicuous. These joggers were also
encountered along the lower path near the water's edge where natural
variation in the path surface is more extreme. The unevenness of terrain
appealed to the fitness challenges required by this form of activity, as well
as the aerobic challenge of using the stone stairs at both Devil's Hole and
the DeVeaux (Whirlpool) stone steps. One couple
of elderly women had easily traversed the native path from Whirlpool State
Park upstream to the stone steps. They were the only ones who recognized me
as a botanist. A naturalist's guide to the crest path would be a good
resource to provide users of the crest paths on both sides of the river, and
it is hoped that this essay may provide useful information for such a guide. Disturbance and Other Problems. Fortunately,
although instances of the establishment of alien or noxious species exist,
they are so infrequent that their removal should not be difficult, especially
when replaced with an appropriate native species. The
planting of Black Locust (Robinia pseudoacacia L.) anywhere in a
native ecosystem is not advised. It is not a restoration tree and its
planting in an area with a restoration mandate, as on the crested areas on
the south side of Goat Island, is to be avoided. These trees, much like Rhus
typhina, the Staghorn Sumach, form clones that are difficult to eradicate
(as on Navy Island, Ontario). The Ulmus
pumila L., Siberian Elm, planted on the urban side of the Robert Moses
Overpass at Devil's Hole should be removed as it is probably at least one of
the Mother Trees whose seeds have become established down in the talus and
basal forest within the gorge. Numerous tree species, such as Box Elder (Acer
negundo L.), Horse-chestnut (Aesculus hippocastanum L.), Norway
Maple (Acer platanoides L.) and Honey Locust (Gleditsia triacanthos
L.) have found their way into the lower gorge slopes from streets above and
the lower slope forests need to be protected. Buckthorn
(Rhamnus cathartica L.) that crowd the crest along the fence, is the
number one enemy of natural or passive regeneration schemes, the number one
invasive species in both natural and disturbed areas. Anywhere and everywhere
this shrub should be eradicated. In any ecotourist program, the dominance of
invasive taxa within a world-class ecosystem is detrimental to the quality of
the visitor experience and a threat to the long-term viability of the plant
communities that the natural-history tourist has come long miles to
experience. To those familiar with nature, Buckthorn is easily recognized and
a blow to the aesthetic enjoyment of the woodlands. One
escaped shrub of the alien English Hawthorn (Crataegus monogyna Jacq.)
was seen. Unlike the above species, removal of this plant should be no
problem at all. This is also true of the single instance of the European Ash
(Fraxinus excelsior L.). The same may be said of the Honeysuckles, Lonicera
tartarica L. or L. morrowii Gray). I suspect that the reason the
Honeysuckles are such an overwhelming nuisance in the talus slopes upstream
is that they were planted abundantly a long time ago and have had over a
century to develop their populations. Orchard
Grass (Dactylis glomerata L.) flourishes in the unmown open areas in
the south sector of Whirlpool State Park, where individual culms can rise as
high as five feet in dense lawns with other weedy species. Here and
there the parks administration has cleared away the crest vegetation to
provide spectacular views of the Niagara River gorge from a vantage point at
least two hundred feet above the water's surface. These vantages were
identified and established nearly a century ago, and enhance the interesting
winding character of the crest path and the fence along it. The path itself,
from observing what is probably the only remaining remnant of the aboriginal
crest, follows a natural trail made by animals who migrate along the crest,
quite close to it, and around which they would excavate their burrows. The
ever-present chipmunk population that can be heard chipping most likely makes
good use of these crest trails. Problems
occur, however, when the cutting for views is indiscriminate and too
extensive. It is a disappointment in these areas to find weedy thickets of
Buckthorn and Garlic Mustard (Alliaria
officinalis Andrz.) amidst the native species. This, together with the
planting of inappropriate, weedy trees and shrubs as well as the removal of
old trees, creating light-wells, or having the area between the crest and the
Parkway too narrow to develop a forest canopy, contribute to a degradation of
this native woodland. One good
strategy when cutting over an area periodically, is to return later in the
season to cut away the weeds that will re-grow, and leave the native species
that re-grow with them. This is reminiscent of the biblical parable of the
tares and the wheat. Let both grow up, but remove the weeds before they set
seed, leaving the native species to establish themselves undisturbed. This
woodland habitat, disturbed as it is, is remarkably self-sustaining if only
shocks to the balance of shade and light were not made, nor interference
allowed with the structure and population mix of native species.
This
old stone bridge spans a water course that is dry due to construction of the Parkway.
To restore stream function at this site would be consistent with ecological
restoration objectives and would return some of the pre-Parkway moisture
regime to the gorge slopes below. Note the strength of the September sunlight
in canopy-free areas adjacent to the Parkway in the distance and the weedy
meadow generated by this condition. The stone
bridge over a dried-out stream bed is charming to come across along the hike,
and one might expect that a few carefully placed old logs or river stones of
native rock would be welcome places to rest and eat lunch. It is unfortunate
that, due to construction of the Parkway, as in other areas along the crest,
such as at Devil's Hole (Bloody Run Creek outlet) and the natural Gill Creek
outlet downstream near Artpark to mention only two, that the natural drainage
as waterfalls or seepage through bedrock is diverted, and the channels and
coves are dry and weedy from salt runoff in winter. To re-establish the
outflow at this stone bridge along the crest trail would be a good
restoration target. Suggestions 1. To protect the canopy, the careful removal of ecologically
inappropriate trees: Black Locust (Robinia
pseudoacacia), Siberian Elm (Ulmus
pumila L.), Norway Maple (Acer
platanoides L.) is advised, and replacement with native stock (Oaks,
Hickories, Walnuts). 2. Since Ginkgoa biloba does
not grow spontaneously, it is benign. Its planting should, however, not be
made in restoration areas. 3. Although the Washington Hawthorn (Crataegus phaenopyrum Medic.)
does not appear to be spreading (there is a colony of this shrub abundantly
growing in the middle and northern old sections of the upper crest of Devil's
Hole beyond the cove area, possibly from suckers) planting of this
inappropriate tree should be ended and greenhouse-grown native species used
or selective transplants from demonstrably regenerating areas (old fields). Native
Hawthorn species in the Niagara area: Crataegus
crus-galli, C. puncata, C. mollis, C. succulenta, C.
chrysocarpa and C. flabellata.
All of these shrubs can be found with various frequencies throughout the
Niagara parklands, a good suite of them at Buckhorn Island in the shrubby
regeneration areas around the Interstate 90, and abundant in non-park areas
such as north of the Youngman Highway (I 290) east of the South Grand Island
Bridge, for example. 4. To restore and enhance the ecosystem either with or without the
removal of the Parkway, primary consideration should be to reestablish the
trees to protect and buffer the canopy layer. Based on information to be
presented in a future posting, the canopy effect should not, however, be as
dark as that in the uncut, old-growth woods in the upstream section of
DeVeaux College woods. What is needed is a more open canopy producing a
dappled light exposure on the ground that is conducive to a diverse shrub
layer. This layer would include various Hawthorn species, those of Dogwood (Cornus spp.), of Witch Hazel and
others that can be determined from various publications presently available. The
advantage of the prevalence of tree species whose fruits are of the nut
variety makes harvesting these fruits easy for both technical and amateur
involvement in reforestation with genetically authentic Niagara stock. A nut
harvest can be employed in germination and growth efforts in greenhouse
contexts that abound in the Niagara region on both sides of the Niagara
River. It would not take an enormous number of trees to implement a viable
restoration project. Amateurs
and professional nut growers alike can experiment all they like germinating
Oak, Hickory, Black Cherry and Walnut nuts and drupes from the gorge crest
crop. The problem would be to reestablish such stock within a professionally
viable restoration plan; the staff and plan are yet to be established, as
well as the authority to do so. With or
without the removal of the Parkway, trees can be established along the median
strip areas between the north and southbound lanes, on the verges bordering
the blacktop and even to involve homeowners whose back lots abut on the
Parkway to replace their weedy tree species with local native material.
Cooperation from the street department of the City of Niagara Falls in
planting such trees along streets near the gorge rim can be developed and
encouraged. Niagara University, which has an enviable location and
association with the Niagara River gorge can take a leadership role in
restoring areas on campus, or simply growing stock from native fruits and
establishing them on campus, in cooperation with their grounds maintenance
department. The
grounds of the New York Power Authority, also situated at the gorge crest
could benefit from using native-grown tree and shrub material in transforming
their lawnscapes in and around the forebay and penstock area, the public
information facility built over the gorge crest, the transformer area and
south of this, the naked areas along the Robert Moses Parkway by the water
intakes. A nursery in fact could be established in these blighted areas where
implementation experiments could be performed and where sprouted material
could be cultivated until mature enough for transferal to critical areas
along the gorge. By that
time a legitimate plan for restoration with implementation authority could
have been developed and initiated. It is rather urgent to begin taking such
steps as the tree species in question are notoriously slow growers, unlike
Maple species, for example. Young
trees are an important component of the missing herbaceous and shrub layers
under the canopy along the crest. As such they contribute an important
element to recovering the original structure of the crest flora (the shrub or
intermediate layer between the grasses and flowering plants and the tree
canopy). Note that
there is nothing to prevent private and municipality partnerships in the area
surrounding the gorge in generating and establishing native stock on private
and community land. 5. Thought should be given to the careful reintroduction of the
White Pine into the crest canopies in the public lands along the Niagara River.
Although it is presumed that most of the absence of this tree is due to the
local logging industry that collapsed with the deterioration of the forests
of the Niagara Region, when the industry moved westward into states such as
Michigan, some consideration should be made that this tree succumbed to the
White Pine Blister Rust. Although species of Ribes do occur in the Niagara gorge flora, it is the European Ribes introduction that is targeted by
governmental quarantines. Surveys of
recent mortality of Eastern White Pine in natural habitats in the
northeastern United States indicate that the mortality percentages due to
this disease are quite low. Specimens of White Pine occur on Goat Island
(these may be introductions) without apparent disease, even though Ribes grows on the island and even
though the trees are subjected to prevalent moisture from the spray zone of
the falls in late summer and early fall, a time when White Pine, especially
young trees, are vulnerable to infection. Further
down in the dappled shade along the drier crest, especially at Whirlpool
Point on the upper and lower banks where White Pine proliferated, it would
seem that a re-introduction might be desirable. Note
should be made of the presence and expanding populations of Barberry (Berberis vulgaris L.) along the crest
and elsewhere in the public lands. This is the alternate host of the stem
rust of wheat and all such wild (and horticultural) establishments are
recommended to be destroyed. This does not include the common foundation
shrub Berberis thunbergii DC., also
growing spontaneously in the parklands, and which is not a host for this
disease. 6. The canopy is never to be interrupted as to allow light-wells,
or areas with intense insolation. to occur. These promote the development of
lawn or meadow species, primarily of a weedy nature. 7. The native herbaceous species seen are typical of the ancestral
species composition of the crest flora. Their population expansion and
reestablishment elsewhere along the crest is to be encouraged in restoration
plans. 8. It is strongly suggested that the path never be paved.
Paving would encourage the development of weeds along its borders as well as
erosion as runoff from rains and melting snow would be channeled along
pavement margins. The unpaved condition adds much to the perception of a
rural experience, the intervals of clay soil and gravelly, stony additions or
exposed soils contributes to the variety of the path experience. 9. Suggested areas that might prove useful to provide a template
for a restoration plan involving the physical or active emplacement of
genetically local native species into what might be close to original
ecological conditions might be observed by analyzing the structure of: a. Both the upper (deep soil) and lower
(shallow soil) woods facing the Parkway at DeVeaux State Park; b. a relatively undisturbed woodland parcel
to be posted; c. the community that persists in the
narrow strip that persists between the path and its fence and the gorge rim;
and, d. other general areas on both sides of the
Niagara River that appear to be useful in providing appropriate data,
historic descriptions of the area, community structures in similar situations
(wooded calcareous gorge crests facing the western sun and the prevailing
westerlies). Similarities may be sought in other areas in New York State in
the Appalachian Oak-Hickory Forest community association described by Reschke
(1990). Provisional Species List for September
23, 2004 Native Trees (happily a robust
assemblage): American
Basswood (Tilia Americana L. Black
Cherry (Prunus serotina Ehrh.) Black
Walnut (Juglans nigra L.) Hop-hornbeam
(Ostrya virginiana (Mill.) K. Koch Paper
Birch (Betula papyrifera Marsh. Pignut
Hickory (Carya glabra (Mill.) Sweet Red Oak (Quercus
rubra L. Shadbush (Amelanchier
sp.) Shagbark
Hickory, ICarya ovata (Mill.) K. Koch Small-fruited
Hickory (Carya ovalis (Wang.) Sarg. Sugar
Maple (Acer saccharum Marsh.) Tulip
trees (Liriodendron tulipifera L.) White Ash
(Fraxinus Americana L.) White Oak (Quercus
alba L.) Alien Trees (surprisingly low in
frequency of occurrence): Black
Locust (Robinia pseudoacacia L.) European
Ash (Fraxinus excelsior L.) European
Bird Cherry (Prunus avium L.), Ginkgo
tree (Ginkgoa biloba L.) Honey
Locust (Gleditsic triacanthos L.) Little-leaved
Linden (Tilia cordata Mill. Norway
Maple planted (Acer platanoides L.) Siberian
Elm (Ulmus pumila L.) Native Shrubs (too few examples and all
on the far side of the fence): Red-osier
Dogwood (Cornus stononifera Michx.) Round-leaved
Dogwood (Cornus rugosa Lam.) Witch
Hazel (Hamamelis virginiana L.) Alien
Shrubs (far too many): Buckthorn
(Rhamnus cathartica L.) English
Hawthorn (Crataegus monogyna Jacq.) Honeysuckle,
Tartarian (L. tartarica L.) or Morrow's Honeysuckle (L. morrowii Gray) Washington
Thorn (Crataegus phaenopyrum
Medic.) Native Vines: River
Grape (Vitis riparia Michx.) Virginia
Creeper (Parthenocissus vitacea (Knerr) Hitchc ) Native Herbs: Arrow-leaved
Aster (Aster sagitifolius Willd.) Blue-stemmed
Goldenrod (Solidago caesia L.) Early
Goldenrod (Solidago juncea Ait.) Early
Meadow-rue (Thalictrum dioicum L.) False
Solomon's Seal (Smilacina racemosa (L.) Desf.) Heart-leaved
Aster (Aster cordifolius L.) Smooth
Aster (Aster laevis L.) Smooth
Rock Cress (Arabis laevigata (Muhl.) Poir.) Tall White
Aster (Aster simplex Willd.) White
Snakeroot (Eupatorium rugosum Houtt.) Zig-zag
Goldenrod (Solidago flexicaulis L.)
Alien Herbs (gratifyingly few in
number and occurrence): Common St.
John's-wort (Hypericum perforatum L.) Garlic
Mustard (Alliaria officinalis Andrz.) Native Grasses: Bottle-brush
Grass (Hysterix patula Moench) Alien Grasses (abundance consistent
with lawn maintenance beneath the canopy): Canada
Blue-grass (Poa compressa L.) Orchard
Grass (Dactylis glomerata L.) Kentucky
Blue-grass (Poa pratensis L.) Meadow
Blue-grass (Poa nemoralis L.) Fungus populations and Chipmunks
were also noted.
Summary Unlike
other areas along the seven-mile length of the gorge crest on the New York
State side of the Niagara River, the crest section between Devil's Hole State
Park on the north and DeVeaux (Whirlpool) Steps to the south, at the north
extension of Whirlpool State Park, retains many of its original tree
populations, a condition essential to a credible plant community restoration.
Due to the high number of nut-bearing tree species, this woodland community
is designated as most like the Appalachian Oak-Hickory Forest community in
the Forested Uplands section described by Reschke (1990). There is much
ecological information present in this section of the crest to provide a
template for environmental restoration should the Robert Moses Parkway be
removed, and even if this were not to eventuate, to provide a template for
more appropriate replacement and maintenance regimes by the several
government administrations that maintain the area in the public interest. Acknowledgement This
manuscript has benefited by a review by Bob Baxter. Bibliography Reschke, Carol. 1990. Ecological
Communities of New York State. New York Natural Heritage Program, N.Y.S.
Dept. Environmental Conservation, Latham, New York. |
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