New York Natural Heritage Program
Large Grass-leaved Rush
Juncus biflorus Ell.
Monocots
Juncus biflorus inflorescence Robert H. Mohlenbrock USDA-NRCS PLANTS Database
Family: Rush Family (Juncaceae)

State Protection: Endangered
listed species are those with: 1) 5 or fewer extant sites, or 2) fewer than 1,000 individuals, or 3) restricted to fewer than 4 U.S.G.S. 7 minute topographical maps, or 4) species listed as endangered by U.S. Department of Interior.

Federal Protection: Not Listed

State Rarity Rank: S1
A State Rarity Rank of S1 means: This plant is endangered/critically imperiled in New York because of extreme rarity (typically 5 or fewer populations or very few remaining individuals) or is extremely vulnerable to extirpation from New York due to biological factors.

Global Rarity Rank: G5
A Global Rarity Rank of G5 means: This species is demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.


Did you know?
You may not find this species in some plant books because it is often lumped under other species, usually Juncus marginatus. In New York it is recognized as a separate species based upon work done by W.N. Knapp on the status of Juncus longii (Weldy, Troy and David Werier 2010).

State Ranking Justification [-]
There are three existing populations but no detailed surveys have been done to determine population size and quality. There are 15 historical records from the early 1900s through 1963 that need to be resurveyed.

Short-term Trends [-]

Long-term Trends [-]