WSU Clark County Extension

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Singleseed Hawthorn

Scientific name: Crataegus monogyna

Type:Invasive plants
Plant Requirements
Zone:4 to 8
Sun:Full sun
Plant Characteristics
Height:30 ft
Width:20 ft
Bloom:Spring flowers
Bloom Time:May
Bloom Color:White
Additional Characteristics



Wildlife value

Description Singleseed Hawthorn is considered an escaped Northwest invasive plant which should be controlled.

This Northwest native is a medium-sized deciduous tree that grows to 20’-30’ tall with a width of 20’. Mature trees have a densely branched rounded crown. Branches tend to be slightly pendulous.

Leaves are 3” long, simple and have 3-7 lobes. They are arranged in an alternate fashion on the twigs. During the growing season the leaves have a rich green color. The cultivar ‘Inermis Compacta’ turns a brilliant red to orange in the fall.

Flowers are small and white, and are arranged in corymbs. Bloom appears in May and petals are retained for slightly more than a week.
Flowers give rise to red, ½” wide pome (apple like) fruit which contain a single seed. The fruit ripen in September and provide the local song birds with fruit during the winter.

Thorns can be up to 1” in length.

Singleseed Hawthorn is widely adapted to most sites, especially ones which are wet. Often considered an invasive since it sets so many seeds which are dispersed by the birds. Dense thickets can form which can choke out other vegetation. In England this species has been intentionally planted to form hedgerows to keep farm animals from crossing into adjacent pastures.

Generally resistant to leaf spot.
For assistance, contact Dr. Charles Brun (, (360) 397-6060 5701
Computing and Web Resources, PO Box 6234, Washington State University, Pullman WA 99164-6234