Himalayan Hazelnut

Trees to 20 m tall; trunk to 30 cm d.b.h.; bark dark gray or gray, fissured. Branchlets purplish brown, pubescent, sometimes stipitate glandular, glabrescent, with scattered, minute lenticels. Petiole 1-3.5 cm, densely pilose when young, glabrescent; leaf blade ovate-oblong, obovate-oblong, obovate, or elliptic, 5-15 × 3-9 cm, papery, abaxially bearded in axils of lateral veins, pilose and sparsely glandular, adaxially sparsely pilose especially along impressed midvein when young, base very obliquely rounded or subcordate, margin sharply and doubly mucronate serrate, apex long acuminate to caudate-acuminate; lateral veins 8-14 on each side of midvein. Male inflorescence ca. 2 cm; bracts broadly ovate, tomentulose, apex acute to acuminate; anthers purple. Female flowers 4-6 in a cluster; bracts campanulate, densely pubescent, sometimes stipitate glandular, with laciniate segments forming branching, pungent spines. Nut ovoid-globose, subcompressed, 1-1.5 cm in diam., apex pubescent. Fl. May-Jul, fr. Jul-Sep. 2n = 22.

Himalaya (Nepal to Bhutan), Assam, Tibet, N. Burma, W. China.

SE Gansu, Guizhou, W Hubei, Ningxia, Shaanxi, E and SW Sichuan, Xizang, Yunnan [Bhutan, NE India, N Myanmar, Nepal, Sikkim].

2600-3200 m

Forests on mountain slopes; 1500-3800 m.

Flowering from May to July; fruiting from July to September.

Corylus ferox var. ferox is close relative of Corylus ferox var. thibetica, but differs from the latter in its scales of buds white villous (vs. glabrous), leaves ovate-oblong or obovate-oblong (vs. obovate or elliptic).

Corylus ferox is occurring in Guizhou, SW Sichuan, NW and W Yunnan of China, Bhutan, Nepal, Sikkim.

The phylogenetic relationships of the genus Corylus (Betulaceae) were investigated using sequences of the internal transcribed spacer regions of the nuclear ribosomal DNA and the chloroplast matK gene (Erdogan and Mehlenbacher, 2000). The two genes gave different results. In the ITS region, Corylus ferox formed the basal-most branch of the Corylus clades, the strict consensus tree was congruent with the results of interspecific hybridization relationships and morphological classification. Two clusters appeared on the strict consensus tree in the matK sequence, one with Asian and European species, and the other with North American species.

Trees to 20 m tall; trunk to 30 cm d.b.h.; bark dark gray or gray, fissured. Branchlets purplish brown, pubescent, sometimes stipitate glandular, glabrescent, with scattered, minute lenticels. Petiole 1-3.5 cm, densely pilose when young, glabrescent; leaf blade ovate-oblong or obovate-oblong, 5-15 cm long, 3-9 cm wide, papery, abaxially bearded in axils of lateral veins, pilose and sparsely glandular, adaxially sparsely pilose especially along impressed midvein when young, base very obliquely rounded or subcordate, margin sharply and doubly mucronate serrate, apex long acuminate to caudate-acuminate; lateral veins 10-14 on each side of midvein. Male inflorescence ca. 2 cm; bracts broadly ovate, tomentulose, apex acute to acuminate; anthers purple. Female flowers 4-6 in a cluster; bracts campanulate, densely pubescent, sometimes stipitate glandular, with laciniate segments forming branching, pungent spines. Nut ovoid-globose, subcompressed, 1-1.5 cm in diameter, apex pubescent.

The chromosomal number of corylus ferox is 2n = 22 (Thompson et al., 1996).

Growing in forests on mountain slopes; 1700-3800 m.

Corylus ferox, the Himalayan hazelnut or Tibetan hazelnut, is a species of hazel native to the Himalayas of eastern Asia.