Native wetlands of Pennsylvania
How many of us are surrounded by wetlands, not knowing what exists there and what purpose they serve. According to DCNR, wetlands are defined as “areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions, including swamps, marshes, bogs and similar areas.” They are considered a body of water, which are included in the definition of regulated waters of the Commonwealth.
There are many identifying species of wildlife and aquatic life that grow in the wetlands, some of these are beneficial, and some are more invasive and need to be managed. Ecological restoration and environmental science are growing careers. Jean Devlin who is an intern this month with the US Army Corp of Engineers at Ives Run in Tioga, PA explained that the focus here is on three very invasive plants: the Japanese knotwood, wild Honeysuckle, and the Russian Olive. “These plants have taken over most of the edge where forest and field might meet,” she said. Devlin chose Pennsylvania because she said there are some unusual species here such as the osprey and bald eagle.
DCNR is enforcing strict standards to preserve natural areas large enough to support viable populations and ecosystems. “It is equally important to maintain corridors of natural landscape traversable by wildlife.”
Devlin explained that wetland replacement and mitigation should be used only as a last resort. “We need to improve wildlife and manage these species better,” she said. “We manage these plants actively,” she added. “We will never get rid of them.” Devlin is also working with the Student Conservation Association through the Army Corp of Engineers.
With useful illustrations and descriptions Devlin explained the taxonomy of mainly grasses, sedges and rushes that are native to the wetlands of this area. Their identification and morphology are often determined by the shape of the seed. For example, a Cyperaceae, the Sedge Family, is identified by sac like structures that hold the seeds. Many produce flowers that are perfect or unisexual. “We have mostly grasslands here and piny woods, as opposed to coastal marshes,” she explained.
Cattails are a common wetland and pond plant in Pennsylvania. They grow up to six feet tall, with ribbonlike leaves that taper to a point. Native plants are always the best choice for use in landscapes, restoration projects, storm water projects, and naturalized areas. Ferns also grow well in wetland soils and provide beneficial habitats for wildlife. Look for plants that will absorb nitrogen and phosphorus.
Devlin who hopes to work as a consultant in environmental science and is also working with AmeriCorp can identify the Wetland Codes established under the US Fish and Wildlife Foundation. Blades of grasses allow some to grow taller than others, and some are beneficial along the streams, maintaining erosion. “The sedges have edges, and the rushes are round,” said Devlin. “Grasses are the most difficult to identify because there are so many characteristics, some not as prominent.”
In the spring the wetlands flourish and seeds are released later in the season. “In August, we start to dig them out.” The Japanese Knot Weed is very invasive and chokes out the natives. Recklessly it grows along stream banks. Permits from DEP and DCNR are acquired to spray it with a special herbicide near aquatic areas.
Wild honeysuckle is also invasive, although it does have a nice scent and attracts pollinators. Some plants such as the bald cypress tree are not native but became part of the wetlands because their root systems can grow in and above the water where it gets the right amount of oxygen.
Thousands of specimens are stored in wetlands. This time of year orchard grasses can be seen and most of the grasses are annuals. Some of these specimens are preserved on plant presses. “It takes 7 days for a wetland plant to dry out completely.”
Also take caution when exploring wetlands. Some plants such as wild parsley can cause welts and shouldn’t be touched according to Devlin. “It is a noxious weed.”
Restoration work can be quite costly, especially when replacing with non-invasive species. “With ecological restoration, we would rather create natural areas.” Public outreach is important to preserve wetlands and not pollute things. There are many emergent plants that grow above the water. Culverts and weirs are used to control water levels. Invasive species are managed on a 5 year rotation plan, and massive acres are mapped and walked before spraying.
DEP has implemented the Pennsylvania Wetland Replacement Project to assist permit applicants to meet the wetland mitigation requirements in order to maintain and protect the significant resources. For more information visit plants.usda.gov.