Pseudotsuga sinensis
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This genus has been sponsored and new text is being prepared, with publication expected in 2023.
Recommended citation
'Pseudotsuga sinensis' from the website Trees and Shrubs Online (treesandshrubsonline.
Genus
Infraspecifics
An evergreen tree described by its discoverer as ‘grand et superbe’ in the wild state; young shoots brown, minutely downy; winter buds brown, non-resinous. Leaves mostly in two opposite rows, notched at the end, 3⁄4 to 11⁄4 in. long, 1⁄16 to 1⁄12 wide, furrowed above, with two whitish bands of stomata beneath. Cones 13⁄4 to 21⁄4 in. long, 1 to 11⁄4 in. wide; the bracts reflexed, three-lobed, the middle lobe 1⁄8 to 1⁄4 in. long, the side ones shorter.
Native of south-west and eastern-central China; discovered by the French missionary Maire in N.E. Yunnan, growing on limestone at 8,500 ft elevation; introduced by him in 1912 to Chenault’s nursery, Orleans. More recently it has been found farther to the north-east, in Anhwei and Chekiang, and also in Szechwan. Plants were imported into Britain from Chenault in the 1920s, but they proved to be very sensitive to spring frosts and most of them were killed while still young.
From New Trees
Pseudotsuga sinensis Dode
Chinese Douglas-fir
Tree to 50 m (usually much smaller), to 2 m dbh. Bark scaly, greyish brown, becoming grey and rough in older trees. Crown broad, domed or flat-topped. Branchlets slender, firm, grooved, reddish brown, quickly turning grey, minute pubescence in the grooves, later glabrous, leaf scars raised, circular or angular; vegetative buds not or only slightly resinous. Leaves dark green, (1.3–)2.5–4(–5) × (0.1–)0.15–0.2 cm, straight, apex emarginate or obtuse. Male strobili 1–1.5 cm long, yellowish. Female cones pendent, ovoid to oblong, (3.5–)4–6.5(–8) × (2.5–)3.5–5(–5.5) cm, purplish, turning purplish brown later; peduncle with a few leaves attached, 1–2.5 cm long. Seed scales orbicular to reniform, 2.5–3 × 3–3.5 cm. Bract scales ligulate-linear, apex trilobate, 3.5–4 cm long, exserted. Seeds light brown, cuneate-ovoid, wings cuneate to ovoid, 0.8–1.5 cm long. Farjon 1990, Fu et al. 1999c. Distribution CHINA: Guizhou, Hubei, Hunan, Shaanxi, Sichuan, Yunnan; TAIWAN. Habitat Mixed mesophytic forest at low to medium elevations, between 600 and 3300 m asl. USDA Hardiness Zone 8. Conservation status Vulnerable. Illustration Farjon 1990, Fu et al. 1999c. Cross-references B427, K271. Taxonomic note Within P. sinensis, Farjon (2001) recognises three varieties: var. brevifolia, regarded by Fu et al. (1999c) as a distinct species (see above, p. 672); var. gaussenii (Flous) Silba, sunk into var. sinensis by Fu et al. (1999c) (and not known to be in cultivation, as var. gaussenii: K. Rushforth, pers. comm. 2007); and var. sinensis, into which he sinks P. forrestii and P. wilsoniana, as well as several other taxa. Pseudotsuga forrestii is, however, distinct from P. sinensis, separable by its longer leaves and different seed scale characters (Fu et al. 1999c). Keith Rushforth (pers. comm. 2008) also points out that in P. sinensis the leaf is flat on the underside, with acute angled margins, whereas in P. forrestii the margin is rounded so the underside of the leaf is not flat.
var. wilsoniana (Hayata) L.K. Fu & Nan Li
Synonyms
P. wilsoniana Hayata
Flora of China recognises var. wilsoniana on account of its occurrence in Taiwan, with the weak differentiation of its having greyish stomatal bands as opposed to the white ones of var. sinensis. It is restricted to the central mountains of Taiwan, and its geographical separation makes its retention at varietal level tenable. Fu et al. 1999c. Distribution TAIWAN. Habitat Mixed mesophytic forest, between 800 and 1500 m asl. USDA Hardiness Zone 8. Conservation status Vulnerable. Illustration NT671, NT870. Cross-references B423, K271.
Seed of Pseudotsuga sinensis var. wilsoniana has been introduced from Taiwan by recent expeditions – for example, the Edinburgh Taiwan Expedition of 1993 (ETE 112, 149, 150, 157, 162, 177), from which young trees are growing in the Scottish botanical gardens and elsewhere, and collections by Kew (ETOT 7, 61). The ETOT field notes record that it grows amongst rich forest, but only where there is little organic material in the soil (even on bare rock faces). Martin Gardner (pers. comm. 2008) reports that it has been the least successful of the Taiwanese conifers introduced by Edinburgh, requiring warm temperate conditions to thrive. It has not done well in Scottish gardens, but specimens have been outhoused to arboreta in warmer situations such as Muncaster Castle, Cumbria and Foxhill Arboretum, Cheshire, and other locations in England, where some trees have currently reached about 3 m in height. In their early stages they are slow-growing and form broad bushy growth, from which a leader eventually emerges (M. Gardner, pers. comm. 2008). A tree from ETOT 61 seen at Kew in 2005 also lacked an obvious leader, and seemed unhappy there.
The general experience with P. sinensis from mainland China is also that it requires a warm site, with ample moisture through the growing season, and is susceptible to spring frosts, particularly while young (Bean 1976b; K. Rushforth, pers. comm. 2008).
