WSU Clark County Extension

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Caucasian Wingnut

Scientific name: Pterocarya fraxinifolia

Type:Deciduous tree
Plant Requirements
Zone:5 to 9
Sun:Full sun
Plant Characteristics
Height:50 ft
Width:50 ft
Bloom:Showy flowers
Bloom Time:May to June
Bloom Color:Green
Additional Characteristics



Wildlife value

Description A relatively rare tree in the Pacific Northwest, the Caucasian Wingnut is recognized by its three-quarter inch diameter seeds, clustered onto long pendulous strings which hang from the branches.

This is a deciduous tree which grows to 50’ in both height and width. It is considered a fast growing species capable of more than 3’ of new growth each year. It forms a canopy which is rounded and broad-spreading. Leaves are 18” and arranged as an alternate, pinnately compound structure bearing 7-27 ovate leaflets. Each leaflet is 2”-5” long and has sharp toothed edges. The foliage is dark glossy green in summer, before turning yellow in the fall.

Flowering begins in May and extends into June. As the bloom fades, small green winged nutlets develop. The pendulous strings bearing the nutlets can reach 20”in length. The nutlets mature to a brown color during the summer and then persist somewhat into the winter.

This species is easily grown in average, medium well-drained soils in full sun. Though it does best on moist ground, it is considered drought tolerant. It can do well even when the ground is hard and compacted.

No serious insect or disease problems. The extensive root suckers can be problem in a lawn.
For assistance, contact Dr. Charles Brun (, (360) 397-6060 5701
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