A deciduous tree over 100 ft high, unisexual, not resinous, usually of somewhat pyramidal habit (the male at least); trunk often branching low, and forming several erect main branches; secondary branches spreading, pendulous at the ends. Branchlets of two kinds: (1) short, stout spurs, which increase very slowly in length and bear the leaves at the tip; (2) long, free-growing shoots with the leaves alternate. Trees in a stunted or unhealthy state produce only the first type of shoot, and will remain practically stationary for many years. Leaves long-stalked, fan-shaped, tapering from the irregularly jagged, often notched apex to the wedge-shaped base, up to 3 in. deep, about 2 to 3 in. wide, not downy, yellowish dull green, the veins all running lengthwise, and repeatedly forking as the leaf broadens towards the end; stalk slender, 11⁄2 to 31⁄2 in. long. Flowers borne on the short shoots, the males in cylindrical, short-stalked catkins about 1 in. long, consisting of green stamens only, the females on a stalk 11⁄2 to 2 in. long, ultimately developing a yellowish green plum-like fruit 1 to 11⁄2 in. long, surrounded by a malodorous, fleshy layer.
According to ancient Chinese texts, the original home of the ginkgo lay in what are now the provinces of Anhwei and Kiangsu, and it still occurs apparently wild in part of its original habitat, namely in the mountainous region between Anwhei and Chekiang provinces (see further in Li’s fascinating work The Origin and Cultivation of Shade and Ornamental Trees (1963), Chap. 4). In other parts of China and beyond it is known only as a cultivated tree. It is certainly not indigenous to Japan, as is often stated, although it was introduced from there to Europe about 1730, and to England twenty-four years later. It is undoubtedly one of the most distinct and beautiful of all deciduous trees, the leaves being quite unlike those of any other. The popular name refers to their similarity in shape to the pinnules of the maidenhair fern (Adiantum).
Most of the large trees in the British Isles are males but a few female trees have been recorded (see below). The first fruits to be produced in Europe were obtained by grafting of the famous female tree at Geneva on male trees. Female shoots on the old tree at Kew, grafted to it in 1911, fruited abundantly until accidentally pruned off. The female tree has been supposed to be less erect in habit than the male or even to have pendulous branches, but Wilson, who saw numerous trees during his journeys in China, Korea, and Japan, stated that there is no difference in habit between the two sexes.
Although the fleshy part of the fruit has a rancid, evil odour, the kernel of the nut is well flavoured, and esteemed by the Japanese. The ginkgo is best raised from seed, and it requires a deep good soil; when young it is often extremely slow of growth, and although very hardy, is no doubt better suited in climates with a hotter summer than ours. Good seeds are now produced by S. European trees, and offer the best means of propagation.
Of the famous tree at Kew, planted in 1762, the following measurements are on record (all girths at 3 ft): 56 × 9 ft (1888), 62 × 101⁄4 ft (1904); 72 × 131⁄2 ft (1970). This tree was originally planted against a wall of the ‘Old Stove’, built in 1761 and demolished about a century later. The ancient wisteria nearby was originally trained on this structure.
The following are some of the more noteworthy specimens measured recently: Chiswick House, London, 75 × 81⁄2 ft (1964); Knap Hill Nurseries, Surrey, pl. 1859, 62 × 81⁄4 ft (1961); Farnham Castle, Surrey, 75 × 83⁄4 ft (1961); Lydhurst, Sussex, 75 × 6 ft (1971); Linton Park, Kent, pl. 1844, 90 × 81⁄4 ft (1965); Penshurst Place, Kent, 80 × 63⁄4 ft (1954); Panshanger, Herts,pl. c. 1770, 78 × 121⁄4 ft (1969); Peckover, Wisbech, Cambs., pl. 1762, 76 × 111⁄2 ft (1962); Sherborne Castle, Dorset, 74 × 93⁄4 ft (1963); Melbury, Dorset, 79 × 6[3/4] + 43⁄4 ft and another 72 × 9 ft (1970); Oxford Botanic Garden, 83 × 81⁄4 ft (1970); Longleat, Wilts, 69 × 10 ft (1963); Badminton, Glos., two trees, 69 × 73⁄4 ft and 68 × 10 ft (1966); Whitfield, Herefi, pl. 1776, 68 × 121⁄2 ft (1963); Blaize Castle, Bristol, pl. c. 1762, 68 × 121⁄4 ft (1969); Bath Botanic Garden, 80 × 41⁄2 ft, a fine slender tree (1962); Bitton Vicarage, Som., 74 × 93⁄4 ft (1959); Engelfield House, Theale, Som., 80 × 11 ft (1968); Carclew, Cornwall, 80 × 101⁄2 ft (1962); Maerlluch, Radnor.pl. 1820, 72 × 131⁄2 ft, with a triple trunk (1962).
The trees listed above are all male or of unknown sex. The female tree at Bath mentioned in previous editions grows at Glanfield, Weston Park, Bath, and measures 50 × 51⁄4 ft (1962). Other female trees have been located by A. F. Mitchell at West Dean, Sussex; Snowdenham House, Surrey; and The Rookeries, Dorking, Surrey.
cv. ‘Laciniata’ (‘Macrophylla Laciniata’). – Leaves deeply laciniated, wavy at the margins and (according to the original description) 10 in. in circumference (Carrière in Rev. Hort. (1854), p. 412). Raised by Reynier of Avignon in 1840 and put into commerce by Sénéclauze’s nursery.
f. pendula (Van Geert) Beissn. – The epithet pendula has no doubt been applied to many specimens of the ginkgo in which the branches are to a greater or lesser degree pendulous. The cultivar name ‘Pendula’ would belong to the clone first distributed by Van Geert’s nursery in 1862. It was described by Carrière as being weak-growing with a leaning main-stem and pendulous branches.
cv. ‘Pragensis’. – This interesting cultivar is referred to by J. P. Krouman in his article ‘The Trees of Prague’ in Gard. Chron. (Oct. 3, 1969), p. 15. According to Mr Krouman there are two specimens at Prague, one in the Botanical Garden of Charles University and the other in the garden of the Neotitz Palace, both estimated to be 150 years old. The specimen figured has a low, spreading, umbrella-shaped crown and tortuous branches.
f. fastigiata (Henry) Rehd. – Of fastigiate habit. Many named clones with this character are in commerce in the United States.