Kaya [Japanese] (Ohwi 1965).
Synonymy (Farjon 1998):
Several varieties have been described, and although they are not recognized here (pending further information on intraspecific variation in the species), they are briefly noted below.
Branches: Spreading, brown (Ohwi 1965).
Leaves: Linear, 15-25 × 2.2-3 mm, stiff, gradually tapering to a short spinescent apex, abruptly narrowed at subsessile base, deep green and lustrous on ± convex dorsal surface, pale green with 2 narrow pale yello stomatal bands on ventral surface (Ohwi 1965).
Seeds: Narrow-ellipsoid, 2.5 cm long, green with pulple tinge (Ohwi 1965).
Var. radicans is shrubby, native to Honshu mountains. Var. igaensis has shorter (10-18 mm long), abruptly spinescent leaves, with a shorter (2 cm) seed. It is rare, found only in Iga Province on Honshu (Ohwi 1965).
The only trees for which I have seen measurements are ornamental specimens in Capitol Park, Sacramento, California, one of which was 12.6 m tall (41.5 feet tall) with three major trunks, and the other 19.1 m tall (62.5 feet) with five trunks, in 2007 (Arthur L. Jacobson e-mail 2007.08.24). Wilson (1916) provides a photo of a tree that appears to be at least 2 m in diameter. This may be what he describes as "the largest tree of Torreya nucifera I saw in Japan," a specimen "28 m. in height and has a slightly buttressed trunk which measures 5.5 m. in girth at 1.6 m. from the ground;" it was (is?) at Hachiman Shrine, Kamo, in Satsuma province, Kyushu, and was but one of several very large specimens. I believe this tree is located at about 31.766°N, 130.571°E.
I have seen ages of more than 500 years attributed, without supporting evidence, to Japanese trees. Such an age is certainly plausible.
Yields edible seeds and cooking oil. Planted as an ornamental in North America and Europe (Hils 1993). Wilson (1916) wrote that "the wood is yellowish to pale brown, firm and lustrous and durable in water. It is used for making water-pails and for cabinet-work." It was traditionally used to make Go boards and bowls, but the tree is now protected and the wood is sourced only from natural mortality, so fine modern Go boards are mostly made from other stable softwoods with good figure and pale grain, such as species of Agathis or Picea.
Wilson (1916) reports: "in one place only is it common, and that is on Takao-san, a hill some 500 m. high, about 27 miles southwest of Tokyo and in Musashi province," growing with Abies firma. We may hope that it persists in this locality. Wilson also reports impressive trees in the wild on Yakushima Island, and cites Sargent as having found trees with girths of up to 5 m "on the banks of the Kiso-gawa, near Agematsu." Wilson reports impressive trees in cultivation "At Hachiman Shrine, Kamo, in Satsuma province, Kyushu."
This appears to have been the first described species of Torreya, described and illustrated by Kaempfer in 1712 under the name Taxus nucifera, subsequently adopted by Linnaeus into his Species Plantarum in 1753 (Wilson 1916).
The illustration at left is from the first installment of Siebold and Zuccarini's Flora Japonica, issued in 1835. Philipp Franz von Siebold visited Japan from 1823-1829 as a doctor and scientist in the employ of the Dutch East India Company. During this time he collected thousands of plant and animal specimens, many of new species that were later named for him. Among the conifers, he is commemorated by Tsuga sieboldii.
Last Modified 2012-11-23