A modern reference to temperate woody plants, including updated content from this site and much new material, can be found at Trees and Shrubs Online.

Quercus glauca Thunb.

Modern name

Quercus glauca Thunb.

Synonyms

Q. annulata Sm.; Cyclobalanopsis glauca (Thunb.) Oerst.

An evergreen tree up to 50 ft high, or a large shrub; young stems brown or purplish brown, downy at first, soon glabrous. Leaves elliptic, oblong, or narrow-ovate, sometimes broadest slightly above the middle, acuminate at the apex, usually tapered, sometimes rounded, at the base, glabrous above, the underside glaucous and more or less permanently coated with appressed silky hairs, main veins in eight to twelve pairs, prominent beneath, margins of leaf sharply toothed in the upper part; petiole up to about 12 in. long. Fruits one to three in each cluster, ripening the first season; acorns about 34 in. long, about one-third enclosed in a downy cup with six or seven raised rings.

Interpreted in a broad sense, this species has a very wide distribution in E. Asia, from Japan and Formosa through China to the Himalaya, where it occurs in the outer ranges and does not ascend above 5,000 ft; it is also found in the Khasi Hills. It is variable and should perhaps be divided into subspecies. Although first described from Japan, the earliest introduction was from Nepal in 1804. Later the Kew collector Richard Oldham sent it from Japan (c. 1861), and it is also in cultivation from seeds collected by Wilson in W. China. According to him it is the commonest evergreen oak in W. Hupeh and E. Szechwan, where it grows from river-level to 5,000 ft. He described it as a ‘handsome tree with a bushy, flattened-round head of widespreading branches’.

Q. glauca is very rare in gardens and only suitable for the mildest parts of the country. There is an example at Caerhays in Cornwall of 20 × 112 ft (1971) and a slightly smaller one at Exbury, Hants.



From the Supplement (Vol. V)

The specimen at Caerhays, Cornwall, measures 36 × 414 ft (1984).

Genus

Quercus

Other species in the genus