Betula grossa ("Mizume")

Japanese name: ミズメ （水目、水芽）
Scientific name: Betula grossa

[Overview]
A deciduous tree up to 20 m tall, growing in the beech zone of the mountains.
When the trunk or branches are damaged, they give off a distinctive smell similar to methyl salicylate (used in poultices).
The bark is dark gray with horizontally elongated lenticels, resembling that of cherry (sakura).
The twigs at first have sparse long hairs, later becoming hairless and glossy.
Leaves are simple, alternate on long shoots and borne two at a time on short shoots, ovate to broadly ovate, 3–10 cm long and 2–8 cm wide; young leaves are densely covered with long appressed hairs on both sides, which later remain only on the veins of the underside.
The leaf margins have sharp, fine double serrations.
The leaves turn yellow in autumn.
The leaf stalk is 1–2.5 cm long and hairy.
There are male and female flowers.
The male inflorescence is a catkin 5–7 cm long and 0.5 cm wide, hanging from the tips of long shoots.
The female inflorescences are borne upright at the tips of short shoots.
The flowers are wind-pollinated.
The fruiting spike is elliptical, 2–4 cm long and 1–1.5 cm wide, borne upright and containing many nuts.
The nut is 3 mm long with broad wings.

[Uses]
The wood is heavy and hard, and is used for building materials, furniture, shoe lasts and the like.

[Cultivation]
Propagate from seed.
It prefers a sunny place with good drainage and good water retention.
For plants in the ground that have taken root, rainfall is sufficient unless sunny weather continues and the soil dries out.
Apply organic fertilizer around the plant as fertilizer in winter.
There are no particular pests or diseases.

[Notes]
The azusa that was once used as the material for azusa-yumi (bows) used in Shinto rituals and the like is said to be this species.
The Japanese name is said to derive from the watery sap that comes out when the trunk is damaged.
The other name, Mizume-zakura, comes from the resemblance of the wood texture and bark to cherry (sakura).

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