New York Natural Heritage Program
Dwarf Hawthorn
Crataegus uniflora Muenchh.
Dicots

General Description [-]
Dwarf hawthorn is a slender shrub growing up to 2 meters tall. Its twigs have long (2 to 7.5 cm) sharp thorns, and are slender and soft-hairy when young. The leaves are alternate, toothed, and obovate to elliptic or spatulate, shiny above and hairy on the veins below. They are borne on short (2 to 5 mm) hairy petioles. The flowers have 5 white petals, and are borne singly (or rarely in clusters of 2 or 3). The 5 green, toothed sepals persist at the top of the fruit, which are greenish-yellow or red pomes (Gleason and Cronquist 1991).

Best Life Stage for Proper Identification [-]
This shrub can be identified when it is in leaf and also in fruit.

Similar Species [-]
Having only one (or rarely two or three) flowers per cluster distinguishes Dwarf Hawthorn from all other Crataegus species in New York. Most other Crataegus species are larger in size.
Dwarf Hawthorn Images
click to enlarge
The Best Time to See
Dwarf Hawthorn flowers in May before the leaves emerge, and the fruits can remain on the shrubs through September.
J F M A M J J A S O N D
Vegetative Flowering Fruiting
The time of year you would expect to find Dwarf Hawthorn vegetative (blue shading), flowering (green shading) and fruiting (orange shading) in New York.