NATURE’S VIEW
Left: A walking bridge is all that’s left of a trail at the Merrimack River Outdoor and Education Conservation Area after water levels rose and flooded the property temporarily. Right: Growing season is kick-started into high gear after water recedes in the floodplain and sunlight begins to bake the forest floor.
The Silver Maple Floodplain Forest By Dave Anderson
A
rare and special riverside forest community grows not far from downtown Concord on undeveloped floodplains along the Merrimack River adjacent to the Forest Society’s headquarters. Silver maple floodplain forests are unique not only for their relative scarcity, but also due to the historical development pressures and specialized plant communities and wildlife habitats that occur on the rich, silty soil deposited by annual flooding cycles. For more than two centuries, industrial mills built dams in many New Hampshire rivers, including the Merrimack, to provide waterpower and later to control flooding. Changing the historicalfrequency and severity of spring flood events altered soil, plants, and wildlife popula-
20 | FOREST NOTES Spring 2022
tions. Natural flood cycles built rich alluvial soil deposits, which became the most productive sites for agriculture. Industrial and agricultural land uses altered and converted disproportionate percentages of the original riparian floodplain forests to farmlands and mills and industrial centers of growing cities. Undeveloped floodplains often feature the former river channels that form oxbow ponds and seasonal vernal pools, which provide habitat for aquatic plants and wildlife. Wet meadows, thickets, shrubs, and silver maple forests are the original fast food “Miracle Mile,” outlying downtown and rich with protein and carbohydrate calories. Spring and fall bird migrations tend to follow river floodplain corridors with
fruit- and berry-producing shrubs. Ample fish and amphibians feed birds and small mammals which, in turn, feed larger predators and birds of prey. Waterfowl and wading birds—ducks and herons—stalk fish and amphibians. Barred owls and red-shouldered hawks often nest near floodplain wetlands. Migrating birds of floodplains include bank swallows, kingbirds, orioles and kingfishers. Fish, frogs, salamanders, snakes, and turtles breed in and near warm, shallow water. Teeming insects fuel aerial foraging by bats and birds. Mammals particularly well adapted to live along rivers and wetlands include raccoons, muskrats, beaver, mink, and otters. At the Forest’s Society’s Conservation Center, silver maple forests narrow to an
