Description from Flora of China
Quercus stewardiana A. Camus, Chênes, Atlas 1: 12. 1934; Cyclobalanopsis stewardiana var. longicaudata Y. C. Hsu & al.
Trees to 12 m tall. Branchlets glabrous. Petiole 1.5-3 cm, glabrous; leaf blade elliptic-lanceolate to oblong-elliptic, 6-12 × 2-4 cm, sericeous and simple hairy when young, abaxially whitish (browning when dry) and sparsely hairy or glabrescent, adaxially dark green, base cuneate, margin apical 1/2 remotely shallowly serrate, apex acuminate to caudate; secondary veins 8-10 on each side of midvein, abaxially prominent, and adaxially inconspicuous; tertiary veins abaxially inconspicuous. Female inflorescences borne in axil of new shoots, solitary, ca. 2 cm; rachis and bracts brown tomentose. Cupule cupular, 6-8 mm × 1-1.5 cm, enclosing ca. 1/2 of nut, outside whitish pilose but glabrescent, inside grayish brown tomentose; bracts in 5-9 rings, loosely arranged, margin dentate. Nut broadly ovoid, 0.8-1.5 cm, glabrous; scar ca. 5 mm in diam., convex; stylopodium persistent, ca. 2 mm in diam. Fl. Jul, fr. Oct of following year.
* Mixed mesophytic forests on mountain tops and slopes; 1000-2800 m. Anhui, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangxi, Sichuan, Yunnan, Zhejiang