New York Natural Heritage Program
Dwarf Hawthorn
Crataegus uniflora Muenchh.
Dicots
Leaves Stephen M. Young
Family: Rose Family (Rosaceae)

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?
This small hawthorn was first collected in New York in 1868 near Tottenville, Staten Island. It was only collected six more times on Long Island and Staten Island up to July 1919. It was not seen again in New York until 2003 when one small shrub was rediscovered near Kreischerville, Staten Island, a locality where it had been last collected almost 100 years earlier!

State Ranking Justification [-]
There is one existing population in a state park but it is under stress by deer browse and may not be viable. There are six historical occurrences.

Short-term Trends [-]

Long-term Trends [-]