These ranks indicate the relative rarity of natural community types and are assigned by the Vermont Natural Heritage Inventory of Vermont Fish & Wildlife Department.
S1: very rare in the state, generally with fewer than five high quality occurrences
S2: rare in the state, occurring at a small number of sites or occupying a small total area in the state
S3: high quality examples are uncommon in the state, but not rare; the community is restricted in distribution for reasons of climate, geology, soils, or other physical factors, or many examples have been severely altered
S4: widespread in the state, but the number of high quality examples is low or the total acreage occupied by the community type is relatively small
S5: common and widespread in the state, with high quality examples easily found