Mottled soil horizons form in locations where the water table fluctuates over the course of the year. Soils which contain brown or yellow mottles within a grayish matrix are hydric soils when the mottling occurs within 18 inches of the surface. Soil series may be selected based on various geographic areas of responsibility or use, series status, various dates, or the soil classification. NRCS-USDA Soil Survey Division key to soil taxonomy in downloadable format. The Manual is intended primarily for use by soil scientists, but can also be used by workers and students who have limited soils experience.
Plant species vary in their tolerance of wetland conditions.
If a species does not occur in wetlands in any region, it is not on the the National List. Obligate wetland plants include duckweed, water lily, pickerel weed, cattails, wooly sedge, soft-stem bulrush, royal fern, and water horsetail. Obligate upland plants include white pine, white clover, Virginia creeper, christmas fern, and ground ivy. Red maple, poison ivy, switchgrass, and alpine violet are examples of facultative plants. Below are some examples of plants commonly found in Vermont wetlands.