Common Names

Yatsugatake-tohi [Japanese] (Iwatsuki et al. 1995).

Taxonomic notes

This is one of those rare taxa that was discovered, named, and has ever since been known by that name.

Description

Monoecious. Evergreen tree to 20 m tall and 40 cm dbh, with a straight round trunk and long, slender, horizontally spreading branches. Bark smooth and brown on young trees, turning gray-brown, peeling off in thin scales; on old trees black-grey, rough and scaly. Branchlets brown, grooved, glabrous; pulvini stout, 0.8-0.9 mm long. Leaves linear, quadrangular, 8-12 mm long, 1.5 mm across, acute on young branches, obtuse on fruiting ones, pale green, with a prominent stomatiferous band in each surface; resin canals one or two, marginal. Flowers May to June. Pollen cones on previous year's shoots, cylindric, red-brown, with numerous stamens. Seed cones erect, solitary, terminal on previous year's shoots, reddish purple, cylindric, pendulous, 4-8 cm long, 2-2.5 cm across. Seed scales thinly woody, orbicular-obovate, cuneate to base, ca. 15 mm long, 13-16 mm wide, minutely denticulate on upper margin. Bract scales ca. 3 mm long, obovoid, apex acute. Seeds fusiform, black-brown, ca. 3 mm long, 2 mm across; wings pale brown, oblong-obovate, ca. 10 mm long, 5 mm wide (Iwatsuki et al. 1995).

Range

Japan: Honshu, in the Yatsugadake Mountains, where it grows in small groves of 10-20 trees (there are only a few hundred trees in all) or mixed stands on north-facing slopes at 1500-2000 m elevation. Climate is cool, with snowy winters and 1000-2000 mm annual precipitation. There are frequent typhoons, which are a principal disturbance and have reduced the population in historic times. It usually grows with Larix kaempferi, Picea alcoquiana var. acicularis, Picea maxomowiczii, and various angiosperm trees and shrubs (Farjon 1990).

Big Tree

Oldest

Dendrochronology

Ethnobotany

Observations

Remarks

Citations

Shirasawa, H. and M. Koyama. 1913. Some new species of Picea and Abies in Japan. Botanical Magazine (Tokyo) 27: 127-132, pl. 2.

See Also

Farjon 1990 (good line drawings).

Iwata and Kusaka 1954 [illustrations].

Kurata, S. 1971. Illustrated important forest trees of Japan. Vol. 1. Second edition. Tokyo [color plates, range maps].