Alnus matsumurae ("Yahazuhannoki")

Japanese name: ヤハズハンノキ （矢筈榛木）
Scientific name: Alnus matsumurae

[Overview]
A large deciduous shrub or small tree 10–15 m tall.
It is found mainly in valleys and on landslide slopes in the subalpine mountains of heavy-snow regions on the Sea of Japan side, but it is also distributed on the Pacific side.
The twigs are tinged with dark purplish gray and are slightly three-ridged.
Leaves are simple and alternate, obcordate-rounded, 5–10 cm long and 3–9 cm wide, with the leaf tip distinctly notched into a arrow-notch shape.
The leaves are somewhat thick, with 6–9 pairs of lateral veins, and the undersides are tinged with powdery white.
The leaf margins have uneven, low double serration.
The petiole is 1–3 cm long.
There are male and female flowers, which bloom before the leaves unfold.
The male flowers grow on catkins hanging down singly or in pairs at the branch tips.
The male catkins have short stalks.
The male flowers are small and borne in threes beside scale-like bracts; the perianth is 4-lobed and there are 4 stamens.
The female flowers grow on cone-like inflorescences, 2–5 at a time, in the leaf axils below the male catkins.
The female flowers have no perianth.
The fruiting spike is elliptical and cone-like, 1.5–1.8 cm long and 1 cm wide, with the fruits attached to the inner surface of the scales.
The fruit is a flattened nut with narrow wings, and the style remains at the tip.

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