A tree sometimes 90 ft high in N. America, with dark brown bark and non-resinous winter buds. Leaflets five or seven to each leaf, obovate or oval, 3 to 7 in. long, 1 to 3 in. wide, finely toothed, downy on the veins above and much more so over the whole under-surface; the down is frequently reddish brown. Flowers in an erect panicle up to 7 in. long, 2 to 3 in. wide, yellow; petals four; stamens shorter than and hidden by the petals. Fruit roundish oblique, 2 to 21⁄2 in. long, smooth, carrying usually two seeds. It flowers in May and June.
Native of the United States from Pennsylvania to Tennessee and N. Georgia, and west into Ohio and Illinois; introduced in 1764. It thrives very well in the south of England, making a handsome round-headed tree, but attains greater dimensions on the continent. The tallest known when the first edition of this work was published grew at Syon House, Middlesex, and was nearing 70 ft in height. This tree no longer exists, and the tallest specimen known today is one at Kew, which measures 85 × 4 ft (1960). Others of good size are: Abbey Gardens, Bury St. Edmunds, 65 × 61⁄2 ft (1962), and Much Hadham Rectory, Herts., 63 × 81⁄4 ft (1964).
f. vestita (Sarg.) Fern. – Leaflets beneath and young branchlets downy. Found wild in various localities.
f. virginica (Sarg.) Fern. – Flowers red, pink or cream. Found wild in W. Virginia.
A. × hybrida DC. A. octandra var. hybrida (DC.) Sarg.; A. flava var. purpurascens A. Gray; A. octandra var. purpurascens (A. Gray) Bean – A group of hybrids between A. flava and A. pavia, usually to be distinguished from the former by their bi-coloured or reddish flowers, which show the influence of the second parent in having glands as well as hairs on the margins of the petals. They are more tree-like than the hybrids of the A. × mutabilis group. De Candolle's type was taken from a tree growing in the Botanic Garden at Montpelier but the cross seems to have occurred several times in gardens and the seedlings and their progeny distributed under various names. The trees known as “A. versicolor” and “A. lyonii” probably belonged to this group but are little known today. A. flava var. purpurascens A. Gray is a wild form of the cross, with purplish-red flowers, found in the Alleghenies. Specimens of A. × hybrida measured recently are: Arley Castle, Worcs., 60 × 6 ft and Denman College, Berks., 58 × 61⁄2 ft (both 1965).
The name A. flava, long used for this species, was superseded by A. octandra Marshall because the latter, published in 1785, antedated A.flava, which was cited from Aiton, Hartus Kewensis, 1789. Now although this work was not published until 1789, it is known to have been upwards of twenty years in preparation. The botanical work was by Jonas Dryander, who succeeded Daniel Solander as Banks' librarian when Solander died in 1782, and Dryander is known to have used MSS prepared by Solander. Now Mr B. L. Burtt, of the Royal Botanic Garden, Edinburgh, has drawn our attention to the fact that the name A. flava Solander was actually published in 1778 in a catalogue of the trees and shrubs growing in the Edinburgh Botanic Garden that year (Cat. Arb. & Frut. Hort. Edin. Cres. 1778, p. 3). The Catalogue seems to have been prepared by Dr John Hope, who was at that time Regius Keeper of the Edinburgh Botanic Garden, and he evidently received the name and diagnosis from Solander, to whom he may well have submitted material for identification. It is very pleasing to record here the restoration of a name given by one of the first botanists to work on the Kew collections, and, moreover, the man 'who reduced our garden plants to order and laid the foundations of the Hortus Kewensis of his friend Aiton' as his contemporary Sir James Edward Smith said (Select. Corrsp. Linn. & Other Nat. II. 3: 1821).
From the Supplement (Vol. V)
The height of 90 ft given in the original impression of the present edition was altered to 140 ft in the reprints. But this height is attained only by crowded, slender-stemmed trees growing in forest conditions.
specimens: Kew, near Main Gate, 60 × 61⁄2 ft (1976) and, in Pagoda Vista, 62 × 61⁄2 ft (1981), both probably planted 1907 or 1910; Hyde Park, London, near Serpentine bridge, 70 × 6 ft (1981); Holland Park, London, 66 × 7 ft at 4 ft (1981) and 89 × 51⁄2 ft (1985); Victoria Park, London, 72 × 61⁄2 ft (1979); St Margaret's Lake Garden, Twickenham, a superb specimen of 75 × 10 ft (1983); Much Hadham Old Rectory, Herts., 85 × 83⁄4 ft and 72 × 71⁄4 ft (1984); Stowe Park, Bucks., 60 × 7 ft (1981); Denman College, Bucks., 60 × 7 ft at 4 ft (1981); The Abbey, Bury St Edmunds, 66 × 71⁄4 ft (1981); Wardour Castle, Wilts., 62 × 7 ft (1977); Cirencester Abbey, Glos., 62 × 7 ft (1984); Bath Botanic Garden, 72 × 11 ft (1984); Bicton House, Devon, 60 × 51⁄2 ft (1983).
Mention should have been made of f. virginica (Sarg.) (A. octandra var. virginica Sarg.; A. octandra f. virginica (Sarg.) Fern,), in which the flowers are red instead of yellow. Such trees, if in cultivation, could be distinguished from A. × hybrida by the absence of glands from the edges of the petals.
A. × hybrida - specimens: Battersea Park, London, 70 × 73⁄4 ft, 68 × 61⁄2 ft and 70 × 81⁄2 ft (1983); University Botanic Garden, Cambridge, 56 × 51⁄2 ft (1984); Arley Castle, Worcs., 60 × 6 ft (1965); Pittville Park, Cheltenham, 49 × 51⁄2 ft (1978); Singleton Abbey, Glam., 68 × 6 ft (1982); Kilmory Castle, Argyll, 60 × 61⁄4 ft (1976).
For a related hybrid, see under A. glabra in this supplement.