Toxicodendron trichocarpum ("Yamaurushi")

Japanese name: ヤマウルシ （山漆）
Scientific name: Toxicodendron trichocarpum

[Overview]
A deciduous small tree 5–8 m tall, found in damp valleys and on ridges in low mountains and mountainous areas.
It does not branch much.
Young branches are densely covered with soft brown hairs.
The leaves are alternate, odd-pinnately compound, 25–40 cm long, and clustered at the branch tips; each has 7–15 leaflets.
The leaflets are ovate to broadly elliptic, 4–15 cm long and 3–6 cm wide, with entire margins, though young trees sometimes have 1–2 large teeth.
Both leaf surfaces have soft hairs, especially dense on the veins of the underside.
The leaf axis is reddish and densely hairy.
The leaves turn red in autumn.
The plant is dioecious; both male and female flowers are borne in large numbers in panicles 15–25 cm long arising from the leaf axils, and are small, yellowish-green and 5-petaled.
The fruit is an oblate sphere 5 mm in diameter that ripens to yellowish brown and is densely covered with stiff hairs; the outer skin later peels off, exposing a white, waxy mesocarp with vertical stripes.

[Uses]
Wood wax obtained from the fruit (drupe) is used as a raw material, for example as a base for ointments.
The root bark is also used medicinally.
The young shoots can be boiled and eaten.
Like Urushi, it yields lacquer sap, but this is not economical.

[Cultivation]
Propagate from seed.
As long as the site is sunny and well drained, it is not particular about soil and is easy to grow.
For potted plants, water thoroughly when the soil surface dries; for plants in the ground, rainfall is sufficient.
Fertilizer is not particularly necessary.
There are no particular pests or diseases.

[Notes]
Like Urushi, contact with the sap causes a rash, so caution is needed.

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