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Tree to 20 m. Branchlets blackish and covered in greyish brown lenticels. Leaves thick and papery or leathery, 6–15(–24) × 3–5(–7) cm, ovate to elliptic or lanceolate, upper surface glabrous, lower surface glaucous and with thick, waxy, scale-like trichomes, 6–10 secondary veins on each side of the midrib, tertiary veins inconspicuous on lower leaf surface, margins entire, apex acuminate and falcate; petiole 1(–1.5) cm long. Monoecious. Staminate inflorescences paniculate or solitary, 5–7 cm long. Pistillate inflorescences terminal clusters, 3–6(–10) cm long. Cupule 0.6–1.8 cm diameter, covered with reddish or greyish brown, triangular bracts; enclosing between half and most of the nut. Nut globose and with a depressed apex, 1–2 cm long. Flowering May to July, fruiting July to September of the following year (China). Huang et al. 1999. Distribution CHINA: southwest Sichuan, northwest Yunnan; VIETNAM. Habitat Mixed mesophytic forest, in association with Abies and Picea; between 2500 and 3000 m asl. USDA Hardiness Zone 7–8. Conservation status Not evaluated. Illustration Wharton et al. 2005; NT464, NT465.
Among all the recently introduced Lithocarpus, L. variolosus probably offers most promise of horticultural success, apparently tolerating a wide range of conditions and, when happy, growing very fast. The first and principal introduction was another made by the Howick and McNamara team on their Sichuan expedition in 1991. They collected the species twice, under numbers H&M 1404 and H&M 1482, the latter from trees growing with L. dealbatus at the treeline on Mount Luoji (see p. 462). At Quarryhill specimens from H&M 1404 planted in the open on a hot hillside have not really flourished, forming somewhat shrubby, multistemmed low trees, of about 3 m in 2004. A different picture can be seen in the mild, moist climate of Vancouver, however, where specimens from the same gatherings are forming elegant trees of great beauty and showing promise for a magnificent maturity (Wharton et al. 2005, Hogan 2008). When observed in 2004 they were approximately 8 m tall, and by 2007 some had reached over 10 m (P. Wharton, pers. comm. 2007). Interestingly, Peter Wharton observed that the progeny from the two collections have different characteristics in cultivation: H&M 1482 is producing ‘huskier’ trees with broad leaves, while seedlings from H&M 1404 are also vigorous but have narrower leaves, that partially twist to display their pale undersides. The branches are held horizontally from the single, silvery-barked trunk, with the foliage hanging vertically from the twigs. The leaves flush out a bronzed brown, turning to shiny dark green above and rather shiny pale green below, giving a charming shimmery effect in a breeze. As with many species in the genus, L. variolosus flowers and fruits young, freely producing knobbly clusters of its acorns if a group is grown together. It is also doing well in England, with good trees at Kew and the Hillier Gardens. It is easily propagated from cuttings (Hogan 2008), so it should become more readily available over time.