Gymnocladus dioica (L.) K. Koch

A deciduous tree up to 110 ft high, with a trunk 6 to 10 ft in girth, usually branching low down, and forming a narrow, rounded head. Branchlets downy when young, light grey, marked by numerous small scars. Leaves up to 3 ft long and 2 ft wide, bipinnate, the two lowest pairs of pinnae being simple leaflets, but the upper ones composed of four to seven pairs of leaflets; the leaflets are ovate, 11⁄2 to 21⁄2 in. long (the two lowest pairs considerably larger), grey-green and hairy beneath, principally on the veins and midrib. The tree is dioecious, the panicles of the female tree being 8 to 12 in. long, 3 to 4 in. wide, narrowly pyramidal; flowers downy, 3⁄4 to 1 in. long; petals greenish white, calyx not quite so long as the petals, tubular at the base, with five linear teeth. In the male tree the inflorescence is about one-third the length of the females. Pods 6 to 10 in. long, 11⁄2 to 2 in. wide.

Native of the eastern and central United States; cultivated in England before the middle of the 18th century. In its foliage it is perhaps the most beautiful of all hardy trees. It is perfectly hardy in the south of England, but grows extremely slowly, and rarely flowers. It evidently needs more summer heat than it gets here, for there are fine specimens both in France and Germany suggesting in their leafless state the habit and branching of the horse chestnut. In autumn a curious effect is produced by the leaflets falling off and leaving the naked common stalk on the branches for some time. In winter, young trees have a very distinct and rather gaunt appearance, the branches being few, thick, and rough. It likes a deep rich soil and is propagated by imported seeds. The common name is said to have originated through the people of Kentucky and Tennessee at one time roasting and grinding the seeds to make a beverage like coffee.

The largest specimens in Britain so far recorded are all in the south-eastern part of the country. They are: Nymans, Sussex, 55 × 5 ft (1966); Kew 47 × 43⁄4 ft and 37 × 3 ft (1964–6); Dulwich College Road, London, 45 × 2 ft (1957); Linton Park, Kent, 47 × 23⁄4 ft (1965). There is an old tree in the Oxford Botanic Garden which is dying back; it measures 49 × 43⁄4 ft (1970). The best specimen in the country was at Claremont, Surrey; it attained 60 × 7 ft and flowered regularly, but no longer exists. In Eire there is one at Ashbourne House, Co. Cork, measuring 46 × 41⁄2 ft (1966).

From the Supplement (Vol. V)

specimens: Kew, 56 × 51⁄4 ft (1973) and another 50 × 53⁄4 ft (1978); Archbishop’s Palace, Lambeth, London, 52 × 33⁄4 ft (1985); Battersea Park, London, ten trees, the best 48 × 5 ft (1983); Brompton Cemetery, London, 40 × 41⁄8 ft (1983); Dulwich College Road, London, 40 × 3 ft (1976); Linton Park, Kent, 72 × 41⁄2 ft (1984); Nymans, Sussex, 59 × 5 ft (1977); Oxford Botanic Garden, 44 × 43⁄4 ft (1981).