A small thorny tree up to 15 or 20 ft high, with thoms 1 in. long. Leaves mostly obovate, three- or five-lobed, wedge-shaped at the base, the lobes rounded or pointed; toothed, dark glossy green, glabrous except when quite young; 1⁄2 to 21⁄4 in. long, two-thirds to as much wide; stalks slender, 1⁄4 to 3⁄4 in. long. On strong, barren shoots the leaves are often more deeply lobed, and with large, gland-toothed stipules. Flowers white, 5⁄8 in. diameter, produced during May six to twelve together in corymbs, the leaves at the time almost fully grown; calyx and flower-stalks glabrous; stamens about twenty, anthers red; styles two or three. Fruits roundish ovoid, 1⁄4 to 3⁄4 in. long, red, containing two, sometimes three stones.
Native of Europe, including Britain, and one of the two forms (now usually regarded as distinct species) known popularly as ‘may’ or ‘hawthorn’. The other is C. monogyna (q.v.), which is best distinguished by having only one style and one stone in the fruit. Although C. oxyacantha has not broken up into so many varieties as monogyna, to it belong some of the very best garden forms of hawthorn. None make lovelier lawn trees.
f. aurea (Loud.) Schneid. C. oxyacantha var. xanthocarpa (Roem.) Lange – Fruits yellow; occasionally found in the wild. In the first edition of this work, Loudon’s C. oxyacantha var. aurea was transferred to C. monogyna but it has been assumed by most authorities that the yellow-fruited haw known to Loudon did indeed belong to C. oxyacantha. There is no evidence that a yellow-fruited form of C. monogyna has ever been in cultivation at Kew. For C. monogyna fructu luteo see ‘François Rigaud’.
cv. ‘François Rigaud’. – Fruits yellow; branchlets yellowish. The tree at Kew was received from Bruant in 1894 as C. “azarolus” ‘François Rigaud’ but certainly does not belong to that species. It agrees with C. oxyacantha in its foliage but the flowers bear one or two styles and the fruits contain one or two nutlets, which suggests that it may be a hybrid with C. monogyna. This tree appeared in the old Kew Hand-lists as “C. monogyna fructu luteo”.
cv. ‘Gireoudii’. – Late growths mottled with pink and white. Put into commerce by Späth in 1899. Mrs Stachan has a specimen of this variety in her garden near Cranleigh, Surrey, which has made a mound some 12 to 15 ft high and 40 to 45 ft in diameter.
cv. ‘Masekii’. – Flowers double, of a delicate rose. The origin of this variety is not known, but it was put into commerce by Späth in 1899.
cv. ‘Paul’s Scarlet’. – The best of all double-flowered red thorns. It originated about 1858 as a ‘sport’ on a tree of the double pink variety growing in the garden of Mr Christopher Boyd, near Waltham Cross. It was propagated by Wm. Paul and shown by him at the International Horticultural Exhibition of 1866 (C. 0. coccinea plena; C. 0. paulii).
cv. ‘Plena’. – Flowers double, white, changing to pink as they age. Cultivated since the end of the eighteenth century and apparently a single clone. In ‘Candida Plena’, put into commerce by Späth in 1911, the flowers remain pure white.
cv. ‘Punicea’. – Forms with rose-coloured flowers are occasionally found in the wild (see f. rosea) but in this clone they are crimson and the petals larger than in wild plants. It was raised in Scotland and distributed by Loddiges (Bot. Cab., t. 1363, 1828).
cv. ‘Punicea Flore Pleno’. – According to Loudon (Trees and Shrubs, 1842) this thorn, with pink double flowers, was introduced from the continent in 1832. It is probably the parent of ‘Paul’s Scarlet’.
f. rosea (Willd.) Rehd. – Flowers tinted with rose. Such forms are fairly common in the wild.
C. × mordenensis Boom – This name has been published recently for hybrids between C. oxyacantha and C. succulenta. The original form of the cross, named ‘Toba’, was raised at the Morden Experimental Farm, Manitoba, Canada, the first parent being ‘Paul’s Scarlet’. Leaves deeply two- to four-lobed, larger than in the first parent. Thorns shorter than in the second parent, inflorescence glabrous, sepals without glands. Flowers (of ‘Toba’) double, white, ageing to pink.