By far, the most difficult aspect of wetland determination is the vegetation. The general idea is that many plant species like cattails are restricted to wetlands, whereas many others like red maple can grow in both wetlands and uplands. To determine the presence of wetland vegetation, one must first identify the most important species on the site. While a few plant species can be easily identified, many require some knowledge of botany. Unfortunately, many wetland plants like grasses, sedges, and plants in the aster family are extremely difficult to identify to species, and require considerable expertise in plant taxonomy to do so.
Identification is also very difficult in the late fall, winter and spring.
Once the dominant species are finally identified, the determiner consults a table indicating how often each species is found in wetlands. If most of the species in the plant community are normally found in wetlands, the site is deemed to have wetland vegetation. At present, personnel associated with the DER or CE do not provide that service. Instead, determinations and delineations are performed by consultants. Property owners should be aware that there is presently no certification program for wetlands consultants.