Upland Shores Rivershores ctober, 1927, was a wet month in Vermont. Rainfall had been higher than usual. The ground was saturated, and rivers and streams were full. On the first Oday of November, an unusual series of meteorological events began to converge on Vermont. By November 3, rain was falling in unprecedented amounts, and by the end of the day on the 4th, nine inches had fallen in some parts of the state. The already full streams and wet ground could not handle all this water, and the result was the greatest natural disaster in Vermont’s written history: the Great Flood of 1927. Curiously, New Englanders from outside Vermont’s borders do not count the 1927 flood as a major event. There was some damage in neighboring states, but the bulk of the rainfall, and most of the damage, occurred in Vermont. Eighty-four Vermonters lost their lives, 55 of them in the Winooski Valley alone. River towns throughout Vermont keep the history of the Great Flood alive. City Hall in Montpelier, on the Winooski River, is decorated with photographs of water lapping the steps of the Capitol. A marker in Cambridge, on the Lamoille River, shows that the floodwaters reached the second stories of buildings in the village. Gaysville, on the White River, was washed away completely and is remembered only in pictures. The loss of human life and property caused by the flood of 1927 and lesser floods is well documented. Changes to the natural communities of rivershores and floodplains are not as well understood, however. How did the plants and animals of the rivershores respond to so much water? Local lore in the town of Sharon, on the White River, tells us that a huge amount of floodplain land was lost in the 1927 flood. Large areas of open ledge on the riverbank are said to have been laid bare. A 60 acre field became a 40 acre field in two dramatic days. Rivershores, perhaps more than any other natural system, reflect the impacts of short- term events. A flood may, in a few short hours, remove tons of soil that took thousands of years to accumulate. An ice jam in the winter may kill trees and shrubs. Spring floods may leave silt carried from far upstream, covering plants and rock. The natural tendency of a river is to clear anything in its path, either by the sheer force of moving water or, in cold climates, by the more abrasive force of ice. When the waters recede and the ice disappears – that is, for most of the growing season – rivershores are calm, sunny, open places, naturally stripped of trees and shrubs. The only perennial plants that survive the regular abrasion and flooding are the ones with firm roots or rhizomes that hold them tenaciously in place. Annuals survive by sending their progeny out to unknown seed beds downstream. 190 / Wetland, Woodland, Wildland Rivershore plants may deceive the naturalist in summer: long, lacy grasses wave in the breeze, delicate harebell flowers hang from slender stalks, and translu- cent touch-me-not leaves grace waist-high plants. But visit the same riverbank in flood time, and you’ll find the grasses flattened to the ground, harebells reduced to tiny basal parts that hang on in cracks in the rock, and the touch-me-nots long gone, having dispersed their seeds in late summer. Rivershores are dynamic places, and because of the severity of the natural forces acting on them, they are unique in the largely forested northeast. Two rivershore types are described here: Riverside Outcrop and Erosional River Bluff. Five other rivershore communities are technically wetlands. Like many rivers flowing out of the mountains, the Huntington River responds quickly to heavy rainfall and melting snow and has a floodplain that changes frequently. Lakeshores The natural communities that inhabit the shores of our lakes and ponds are as varied as the lakes and ponds themselves. No two are alike. Many lakeshore communities are wet for much of the growing season and are therefore classified as wetlands. On many lakes and ponds, there is practically nothing that can be called shore; forest meets lake abruptly, with no fanfare. It is only where there is something to challenge the forest that one finds open, dry shoreline communities on a lake. Ice challenges the forest by pushing upward onto the shore as a lake freezes, scarring the bark of trees and shrubs, and ultimately killing them. Water challenges the forest in lakes where spring flooding lasts long enough to drown trees. Wind challenges the forest by stressing trees, or by depositing sand and moving it about year after year, as on a beach or dune. We recognize three dry, open communities of lakeshores: Lake Shale or Cobble Beach, Lake Sand Beach, and Sand Dune. Spruce-Fir Northern Hardwood ForestUpland Formation Shores / 191 HOW TO IDENTIFY Upland Shore Natural Communities Read the short descriptions that follow and choose the community that fits best. Then go to the page indicated to confirm your decision. Riverside Outcrop: These are bedrock exposures along rivers and streams, where flooding and ice scour combine with summer drought to keep trees and shrubs from becoming established. Vegetation is very sparse, with plants growing in small patches of soil that accumulate in cracks. Go to page 193. Erosional River Bluff: These are steep, eroding areas of sand, gravel, clay, or silt, on riverbends where natural movement causes continued sloughing of sediments. Go to page 197. Lake Shale or Cobble Beach: These are lake beaches made of coarse fragments such as shale or cobble. They are kept open by spring flooding, ice scour, and wave action. Moisture is not abundant during the growing season, in contrast with Lakeshore Grassland, which is a wetland community. Go to page 200. Lake Sand Beach: These are lake beaches made from finer soil fragments (sand). They are kept open by spring flooding, ice scour, wave action, wind, and regular deposition of new sediments. Go to page 203. Sand Dune: These are always associated with Sand Beaches and are found land- ward of them. They are areas of sand movement due to wind. Vegetation is sparse. Go to page 206. 192 / Wetland, Woodland, Wildland RIVERSIDE OUTCROP ECOLOGY AND PHYSICAL SETTING Riverside Outcrops are places along rivers and streams where bedrock is exposed and treeless. They are most common where waters are swift, such as at narrows, gorges, rapids, and falls. The large rivers, like the Connecticut, Winooski, Lamoille, Missisquoi, and White, have the most extensive areas of Riverside Outcrops. Smaller rivers and streams, with less extensive flooding and less ice to scour banks, tend to have smaller outcrop areas. Although Riverside Outcrops are similar to outcrops that are not near water in their exposure to the heat of the sun and their lack of soil, most are distinct in that they are influenced by river processes. Where outcrops are within a few feet of river level, they are scoured regularly in the winter by ice as it expands and pushes up on the banks, and also in spring as the great floes move downstream on DISTRIBUTION/ABUNDANCE spring floods. This scouring kills most woody plants by Riverside Outcrops are damaging the growing tissue in their bark. Where outcrops found on rivers and streams are within the zone of flooding, high water deposits throughout Vermont, though they are nowhere abundant or sediments in the rock crevices, creating miniature pockets of large. They are found on all alluvial silt or silt loam, soil types that are more commonly the larger rivers, including the found in floodplain forests. These loamy pockets of soil Connecticut, White, West, tend to be nutrient-enriched and hold moisture well, in Black, Ottauquechee, Deerfield, Winooski, Lamoille, contrast to the nutrient-poor soils that develop in place on and Missisquoi, and very some other kinds of rock outcrops. And where outcrops are likely others. Communities near falls, they are bathed in mist, which provides needed with similar groups of species moisture. Valley fog gives Riverside Outcrops added are known to occur in all New England states and in New moisture, too, especially in late summer and fall. York and are likely to occur in Riverside Outcrops can be nearly level to gently sloping, adjacent Canada as well. Out- or they can be completely vertical, as in a gorge. The crop communities on rivers in steeper the slope, the more difficult the accumulation of other parts of North America and the world may rely on soil, and the sparser the vegetation tends to be. Some similar ecological process, Riverside Outcrops are formed by erosion of bedrock over but the species are different. Upland ShoresProfile / 193 RIVERSIDE OUTCROP millennia – this process creates gorges, and ANIMALS in some gorges the exposed rock can be The mammals and birds that one sees far above the present-day river. on Riverside Outcrops are probably more Any kind of rock can form the substrate a factor of the habitat that surrounds the for a Riverside Outcrop. Schists and outcrop than the outcrop itself. Small phyllites line much of the Connecticut, mammals such as river otter and mink will schists and grey limestones are common pass through, moving to or from a river. on the White, and white limestone can be Large mammals may use a riverside outcrop found on the lower Winooski. Granite is as access to water. Shorebirds can be found seen very locally, as on a short stretch of occasionally on rocky shores, though they the West River in southern Vermont and are more likely to feed on muddy shores.