Picea alcoquiana | Threatened Conifers of the World (en-GB)

Pinaceae

Picea alcoquiana (Veitch ex Lindl.) Carrière

Endemic to Japan where logging has caused a considerable reduction in the population

Description

Taxonomic Notes

The IUCN Redlist recognises three varieties of Picea alcoquiana - var. reflexa

(Shiras. & Koyama) Fitschen, var. acicularis (Shiras. & Koyama) Fitschen and the nominate variety. The first, var. reflexa is mainly recognised on the basis of having reflexed cone scales and was first described in 1913 from the Hayakama and Ohi Valleys in Yamanashi and Shizuoka Prefectures. A range wide survey including more than 800 individual trees found that this character varied continuously on individuals and throughout the total population and therefore could not be used to distinguish var. reflexa from the nominate variety (Aizawa & Kaji 2006). In addition, var. acicularis (sometimes referred to as Picea shirasawae Hayashi) has been recognised as a morphological variant of Picea koyamae Shiras. on the basis of its genetic profile (Katsuki et al. 2004). Consequently, neither of these varieties should be recognised.

Distribution

Endemic to the Japanese island of Honshu in the Yatsugatake and Akaishii mountains. In the northern part of its range it occurs as small isolated stands whereas in the south, some 130 kilometers away, stands tend to be larger and more contiguous. It was more widespread during the Last Glacial Period (Aizawa et al. 2008).

Habitat and Ecology

This taxon is a scattered mountain species, occurring at elevations from 700 to 2180m above sea-level. The soils are of volcanic origin and podzolic. The climate is cool, with cold, snowy winters, and wet (annual precipitation 1000 to 2500mm), while typhoons are frequent. The forests on these mountains are mixed coniferous, with Picea jezoensis subsp. hondoensis as the most common of the spruces, Tsuga diversifolia and Larix kaempferi, both also common, Pinus parviflora and Abies veitchii in some areas, A. mariesii usually at higher elevations, and broad-leaved trees, e.g. Betula ermanii, B. grossa, Sorbus commixta, Quercus mongolica var. grosseserrata, Alnus hirsuta var. sibirica, and Prunus maximowiczii.

Human Uses

This is a timber tree of minor importance due to its scarcity, but it has undoubtedly been logged with other spruces (P. jezoensis subsp. hondoensis) and conifers. Much of its wood is processed to pulp for the paper industry, but more specialized uses are furniture making and (in Japan) musical instruments. This species has been introduced to Europe and the U.S.A. but remains uncommon there and mostly restricted to arboreta and some large parks of private estates, where it may still be known under the later name Picea bicolor.

Conservation Status

Global status

Near Threatened

Global rationale

The species as a whole, like its most common and widespread nominate variety, does not meet the criteria for a threatened category, but may come to fall into one if the decline due to logging continues.

Global threats

The main threat to the species, past and present, is logging. This has particularly affected the rarer varieties with their very limited EOO and AOO.

Conservation Actions

Some sub-populations occur in protected areas.

References and further reading

Aizawa, M. & Kaji, M (2006). Taxonomic Review of Picea alcoquiana var. reflexa (Pinaceae) based on cone morphology. Acta Phytotax. Geobot. 57(2):165–175
Aizawa M, Yoshimaru H, Katsuki T & Kaji M. (2008) Imprint of post-glacial history in a narrowly distributed endemic spruce, Picea alcoquiana, in central Japan observed in nuclear microsatellites and organelle DNA markers. J Biogeogr. 35:1295–1307.
Katsuki, T., Farjon, A. & Carter, G. (2013). Picea alcoquiana. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. Downloaded on 08 July 2013.
Katsuki, T., T. Sugaya, K. Kitamura, T. Takeuchi, M. Katsuta & H. Yoshimaru 2004. Geographic Distribution and Genetic Variation of a Vulnerable Conifer Species, Picea koyamae (Pinaceae). Acta Phytotaxonomica Geobotanica 55(1):19-28.
Shimizu, T. 1992. Taxonomy and phytogeography of the conifers, with special reference to some subaline genera (2) the genus Picea. Japanese Journal of Japanese Botany 9:3-11.