New York Natural Heritage Program
Ram's-head Ladyslipper
Cypripedium arietinum Ait. f.
Family: Orchid Family (Orchidaceae)

State Protection: Threatened
listed species are those with: 1) 6 to fewer than 20 extant sites, or 2) 1,000 to fewer than 3,000 individuals, or 3) restricted to not less than 4 or more than 7 U.S.G.S. 7 minute topographical maps, or 4) listed as threatened by U.S. Department of Interior.

Federal Protection: Not Listed

State Rarity Rank: S2
A State Rarity Rank of S2 means: This plant is threatened/imperiled in New York because of rarity (typically 6-20 populations or few remaining individuals) or is vulnerable to extirpation from New York due to biological factors.

Global Rarity Rank: G3
A Global Rarity Rank of G3 means: This species is either rare and local throughout its range (21 to 100 occurrences), or found locally (even abundantly at some of its locations) in a restricted range (e.g. a single physiographic region), or is vulnerable to extinction throughout its range because of other factors.

Did you know?
Like other Cypripedium species, Ram's head Ladyslippers have what's called a "deceptive" pollination system. The flowers' showy petals and odor attracts bees, but produces no reward of nectar. Thus the species must rely on "nave" bees to transfer pollen between flowers before learning to avoid such fruitless efforts.

State Ranking Justification [-]
There are 13 verified occurrences and 26 historical occurrences. Several occurrences first known from the 1980's have not been seen in subsequent visits. Of 5 historical locations visited, none have been rediscovered. The reasons for this orchid's decline, in spite of its fairly broad habitat tolerances, are not well understood.

Short-term Trends [-]

Long-term Trends [-]