Wetland Indicators

Acorns of Quercus ruba (Northern red oak)

Wetland indicator Status

Our catalog lists the wetland indicator status of every species we grow. This is sourced from wetland ratings found in the National Wetland Plant List (NWPL). Wetland indicators provide insight on a plant’s water needs, however be aware that these categories generalize. Species vary significantly within any category. Below are descriptions of each wetland indicator:

OBL (obligate wetland)- Typically only occur in wetland sites. These plants need to be wet. They are often tolerant of flooding but not of drought.
FACW (facultative wetland)- Primarily seen in wetland sites, but known to appear in drier locations as well. These plants can often thrive in saturated soils or soils with average moisture. Generally, they’re drought intolerant.
FAC (facultative)- Typically occur across a wide array of moisture conditions. They can often tolerate wet and dry soils.
FACU (facultative upland)- Primarily found in sites with average to dry soil. These plants like to be on the drier end of the spectrum, but aren’t necessarily as drought-tolerant as the upland plants.
UPL (upland)- Generally do not occur in wetlands. These plants like to be high and dry. They’re often drought-tolerant, but intolerant of flooding.

Cephalanthus occidentalis (Buttonbush)

Wetland indicator status is a classification developed by the U.S. EPA, Fish and Wildlife Service, and Army Corps of Engineers to help categorize plants for conservation and restoration projects. Wetland indicators are a useful tool at Mellow Marsh when we suggest substitutions, since they help us ensure we match water requirements. They can be useful to people browsing our catalogue as they provide a filter for water needs.