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BOTANICAL
EVALUATION OF THE GOAT ISLAND COMPLEX, NIAGARA FALLS, NEW YORK |
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6. SOUTH SLOPE Porter's Bluff formed the western terminus, overlooking the Horseshoe Falls at Terrapin Point, and the eastern one occurred near the center of the First Sister Island. In early pictures, there was a number of native conifer trees which grew on these slopes, including Arbor Vitae (Thuja occidentalis, see species catalogue). Historically, the most serious erosion from high water levels occurred on this side of the Island where around 90 percent of the river's volume was and is still concentrated. "Upon the southern side of this island, where there is an escarpment, the thickness of the superficial deposit is about twenty-five feet. The upper half consists of coarse gravel and sand, with abundance of ... shells" (Hall, 1843). Soils here are "mostly coarse gravel with cobble" (Kindle & Taylor, 1913) and more well-drained than, for example, the north slope with its finer-size sediment (see discussion of north slope). The embankments that run in an east-west direction are the basally eroded bluffs seen in an early depiction of the south side of the Island in a picture published in the 11th annual report of the Commissioners (1895) and duplicated above in the section on erosion. The first road constructed on Goat Island by its first American owners, the Porter family, was washed out here (Porter, 16 Ann Rep Comm, 1900). Erosion control structures were built on the south side by the Porters and replaced throughout the first years of the Reservation, and variously planted. At the time of the Reservation's establishment, the original vegetation appears to have been catastrophically altered due to this erosive process and subsequent slumping of the soil bank. This bank has "at times been slightly undermined by the river, and thus made a graceless inclined plane, with a raw surface and an angular crest," (Olmsted and Vaux, 1887, mistakenly referring to it as the west bank) - the profile of sediments which have slumped from being undercut at the base, disrupting everything rooted in its soil. Olmsted and Vaux suggested sculpturing the profile into rounded crest and base before covering it in "foliage and verdure." T he present wooded aspect of this area is the result of natural regeneration, if the very mature native trees to be seen there today were not planted by Welch and his successors. In 1890, "trees and vegetation upon the southern shore ..." were carried off "causing the bank to look raw and unsightly" (7 Ann Rep Comm, 1891). Funds for cribwork were appropriated, in 1891 and "the raw embankment covered with loam, and planted with vines, shrubs, willows, and other suitable trees .... The damaged bank has been almost entirely covered by vegetation in one season" (8th Ann Rep Comm, 1892). "The space behind the docking and crib-work recently constructed and the cavities in the damaged bank have been filled with dead and decayed wood, taken from the thicket on Goat Island so as to restore as nearly as possible the natural slope of the banks. The filling has been covered with wood mold, loam and a margin of green sward, and the bank planted with 3,317 cuttings, trees, shrubs and vines, comprising 700 cuttings of yellow willow, 110 cuttings of weeping willow, 1,900 cuttings of dwarf willow, thirty-six snow ball trees, fifty-eight purple lilacs, twenty-four white lilacs, nine red cedars, fourteen spireas, twelve euonymus, and 440 Virginia creeper" (8 Ann Rep Comm, 1982). In 1896, there was the "planting out of the cribwork on the southern shore of Goat Island." Pockets were dug in the cribwork and "willows and vines planted," to cover and disguise it (13 Ann Rep Comm, 1897). The largest willows on the south bank today are the White or Crack Willow (Salix alba or S. fragilis) or hybrids, and hence from imported nursery stock originally. In 1911, a trail has been built running from the Horseshoe Fall up along the south bank of Goat Island toward the Three Sister islands, gradually rising from the level of the river to that of the main path and the road above. It made accessible many points from which "new and charming views of the Horseshoe Fall and Canadian Rapids may be obtained and completes the circuit of trails on Goat Island" (28 Ann Rep Comm, 1912). This was the Terrapin Trail - the complement of the Lunar Trail on the north side of Goat Island. It appears that portions of this trail were built through virgin wood "hitherto inaccessible" (28 Ann Rep Comm, 1912). In 1912, "the bank at the upper end of the new Terrapin trail was washing out rapidly with every rain storm. A retaining wall of field stone and cement has been built at this point" (29 Ann Rep Comm, 1913). It is not noted whether construction of the trail itself contributed to this instability. It is possible that portions of the present low strip of land between the embankment to the north and the river on the south was recently created through lowered water levels, and that the plant communities, waterside thickets here are relatively young. This low area may have been created along with the land at Terrapin Point and sodded over, rather than letting native plant communities establish themselves on newly exposed riverbed as they had on the flats south of the southern shore of Goat Island. Originally, dense thickets, attractively decked in winter with frost from the falls, covered the southern embankment as it overlooked the Terrapin Point stairs (16 Ann Rep Comm, 1900, see Terrapin Point section). A conifer element was visible. A later photograph made at the opening of the Terrapin Trail showed a vegetation that was visually impenetrable. As the south slope or embankment is generally south-facing and open to the sun, in addition to being open to incoming moisture from the spray of the Horseshoe Falls, some idea of the former luxuriance of the native vegetation can be imagined, especially near Terrapin Point. If the lawns were eliminated here, the native vegetation would probably be visually striking. The conditions promoting the vegetation here are not present in the north slope except historically, at Stedman's Bluff, overlooking Luna Island, due to the north aspect and darkness, with a correspondingly sparse herbaceous and shrub slope cover. Today the south bank extends from the crest of the gorge on the west end of Goat Island to the stone bridge connecting Goat Island with the First Sister. Many fine old specimens of Ash and Sugar Maple occur here, as do Basswood, Hop-Hornbeam (Ironwood) and Yellow Oak (Quercus prinoides var. acuminata), and an occasional Hickory and Black Cherry. Historically, based on photographs of the southern slope at Porter's Bluff at Terrapin Point, many conifer trees grew here, as mentioned above, but none exist today. It is possible that the central portions of the south slope were totally denuded by soil slumping prior to 1885, and that this entire plant community regenerated since that time. If that is the case, then this is a fine example of the possibility of natural reforestation to climax community from bare and altered sediment. Another example may be seen in the native wooded element on the crest of Goat Island on the west end. There is evidence that areas of the crest have also experienced total forest loss due to slumping. The native woods has always been able to reestablish itself if left alone to do so. Many plantings of alien species are, however, presently being established to replace the older trees: Schwedler Maple or Norway Maple, Small-leaved Linden (Tilia cordata), Black Locust (Robinia pseudoacacia), Honey Locust (Gleditsia triacanthos), and Box Elder (Acer negundo), and others. Lawns are maintained beneath these alien trees, alltogether eliminating the native forest. Everywhere on this slope the Ash is in recovery, seeding itself. Sugar Maple seedlings are visible as well. The vegetated slope is sandwiched between a lawn above with alien trees and weeds and a lawn below, and so many urban species have infested these slopes. One serious problem is the extensive colony of Giant Hogweed (Heracleum mantegazzianum: see note) that has established itself on the shoreline at the water's edge. Attempts to eradicate it have not been successful. The fact that this species produces a highly toxic dermatological reaction in some people, causing scarring blister-burns on the skin, is one reason for controlling this species. The other is that it forms monocultures. The source of these populations is upriver at Buckhorn Island State Park which has a dense population on the water's edge by the north Grand Island Bridge. Removal of the stand on Goat Island will not prevent further reestablishment of this species on Goat Island as seeds come downriver from the State property a few miles upriver. Another population has established itself on Green Island at the water's edge. NOTE: (2004) the report of this
species of Heracleum in 1990 was based on an erroneous determination. All
reports associated with the Goat Island work in 1990 are Heracleum lanatum, a
harmless species, both on Goat Island and upstream at Buckhorn Island. This
species can be reintroduced in the places designated. On the expanse of land parallel to the embankment between the slope and the water's edge a lawn is maintained. At the shoreline, wet thickets have established themselves with native willows, Cottonwood, Trembling Aspen, etc. This appears to be a relatively new community, related in time and event to the creation of the flats communities in the waters south of the island shoreline. Unfortunately here, as well as on the embankment, especially toward the Horseshoe Falls where the spray is heavy, this area is densely populated with Box Elder (Acer negundo), which tends to form monocultures at the expense of species diversity. The source of this infestation is the old trees planted long ago in the upper lawns in view of the Terrapin Point Restaurant. Norway Maple (Acer platanoides) has also infested the wooded slopes. On the river margin, native trees and shrubs are presently being cut back to provide unimpeded access to the water's edge. People walk there to view the water and compact the soil so that eventually both native vegetation and soil are be destroyed as on Goat Island facing the First Sister. Weedy lawn species are recolonizing areas where native vegetation is removed and replaced by lawns. Expansion of mowed areas and continuing to open up the same vistas on the River to visitors probably promotes the experience of sameness here, and does not enhance the visitor experience in addition to destroying a nationally, historically significant native island flora. There are some areas with beautiful pebbly deposits with abundant native shells washed ashore and crayfish. These areas could be protected and interpreted to the public. The area becomes biologically sterile and depauperate where the lawns come to the edge of the land. Weedy taxa include Plantain, Ox-eye Daisy, Chickweeds, young Tartarian Honeysuckle, etc. Visitors are unaware of the heritage they are destroying in their curiosity. If attempts are not made to remove weedy species, and to cease replacing native species with alien trees which become noxious weeds after the mature native trees have been removed, the vegetation here will be constituted of monoculture-forming weeds of no scientific or historic value and lawn-species: Box Elder, Norway Maple, Tartarian Honeysuckle (present all along the slopes), Lilac (Syringa vulgaris), Privet, Burdock (Arctium spp.,), Garlic Mustard (Alliaria officinalis), etc. Native species will be reduced to Goldenrods, Asters, Thistles, Grapevines, etc. For further discussion, see the Flats section. Weedy species associated with disturbance that are replacing the native species include the following: TREES (all escaped from plantings) * Acer negundo BOX ELDER. Heavily infested toward the Horseshoe Falls. * Acer platanoides NORWAY MAPLE. Infestation in one area. * Prunus avium BIRD CHERRY. * Salix fragilis CRACK WILLOW. Dominant tree on water's edge. SHRUBS (all escaped from plantings) * Cornus sanguinea BLOODTWIG DOGWOOD. * Lonicera tartarica TARTARIAN HONEYSUCKLE. Abundant [noxious]. * Rhamnus cathartica BUCKTHORN. Abundant [noxious]. HERBS (alien) * Barbarea vulgaris WINTER CRESS. * Bromus inermis HUNGARIAN BROME-GRASS. * Cerastium sp. CHICKWEED. On rock, shorelines. * Chrysanthemum leucanthemum OX-EYE DAISY. * Cichorium intybus CHICKORY. * Daucus carota QUEEN ANNE'S LACE. * Dipsacus sylvestris TEASEL. * Galinsoga ciliata CILIATE GALINSOGA. * Heracleum lanatum COW PARSNIP. [reports of Heracleum mantegazzeanum are erroneous.] * Hypericum perforatum COMMON ST. JOHN'S WORT. * Lotus corniculatus BIRD'S FOOT TREFOIL. * Lythrum salicaria PURPLE LOOSESTRIFE. Emergent vegetation in the river. * Melilotus alba WHITE SWEET-CLOVER. * Phleum pratense TIMOTHY. * Plantago lanceolata ENGLISH PLANTAIN. * Poa compressa CANADA BLUE-GRASS. On rocks. * Rumex crispus CURLED DOCK. * Solanum dulcamara BITTER NIGHTSHADE. Abundant on slopes. TREES (native) Fraxinus pennsylvanica RED ASH. Abundant. Populus deltoides COTTONWOOD. Dominant trees. Populus tremuloides QUAKING ASPEN. Rhus typhina STAGHORN SUMACH. Ribes sp. CURRANT. [Rosa sp. Thorny, no flowers or fruit. Salix interior SANDBAR WILLOW. Salix rigida HEART-LEAVED WILLOW. Ulmus [americana] ELM. Ulmus rubra SLIPPERY ELM. SHRUBS AND VINES (native) Cornus racemosa PANICLED DOGWOOD. Few. Cornus stolonifera RED-OSIER DOGWOOD. Dominant Dogwood. Physocarpus opulifolius NINE-BARK. Abundant on river margins. Sambucus canadensis ELDERBERRY. Water's edge, single population. Vitis riparia FROST GRAPE. Abundant especially toward the Horseshoe Falls. HERBS (native) Agrostis sp. BENT-GRASS. In undisturbed areas. Allium canadense WILD GARLIC. Asclepias syriaca COMMON MILKWEED. Carex hystricina PORCUPINE SEDGE. Typical where undisturbed water's edge. Cirsium sp. [small and large] THISTLE. Clematis virginiana VIRGIN'S BOWER. Cuscuta gronovii COMMON DODDER. Epilobium [coloratum] WILLOW-HERB. Erigeron strigosus DAISY FLEABANE. Eupatorium maculatum JOE-PYE-WEED. Eupatorium perfoliatum BONESET. Eupatorium rugosum WHITE SNAKEROOT. Galium obtusum BLUNT-LEAVED MARSH BEDSTRAW. Geum canadense WHITE AVENS. Impatiens biflora SPOTTED TOUCH-ME-NOT. Juncus articulatus JOINTED RUSH. Typical where undisturbed water's edge. Lysimachia ciliata FRINGED LOOSESTRIFE. Typical of the thickets. Monarda fistulosa BERGAMOT. Scirpus americanus CHAIR-MAKER'S RUSH. By culvert, showing habitats which could be made. Solidago canadensis CANADA GOLDENROD. Solidago graminifolia NARROW-LEAVED GOLDENROD. BRYOPHYTES (native) Amblystegium tenax. Barbula unguiculata. Fissidens taxifolius. Covers the damp shaded soil below shrubs or trees along wet soil margins. Orthotrichum anomalum. On boulders toward the Three Sisters.
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