The tree on which this name is founded arose in the Segrez Arboretum, France, and was first described in 1880. Three years later Carrière published an account (Rev. Hort., 1883, p. 108) of a very similar hawthorn, which was distributed, and long known as, C. carrierei. In a botanical sense this name must be regarded as a synonym of C. × lavallei, but it is desirable to preserve the name in cultivar form, in order to distinguish Carrière’s plant from the Segrez form. Whether the latter was ever propagated and distributed is not known.
cv. ‘Carrierei’. – A tree of sturdy, leafy habit up to 15 or 20 ft high; young shoots downy, sometimes retaining the down until the second season; thorns few, stout, 1 to 11⁄2 in. long. Leaves obovate or oval, tapered at both ends, 11⁄2 to 41⁄2 in. long, 1 to 21⁄2 in. wide; coarsely and irregularly toothed, glossy dark green above and soon glabrous except along the midrib; permanently downy beneath, especially on the midrib and veins; stalk 1⁄4 to 3⁄4 in. long. Flowers white, nearly 1 in. across, produced in June in erect corymbs about 3 in. in diameter. Flower-stalks and calyx very woolly, the lobes of the latter glandular-toothed, linear-lanceolate; stamens twenty; styles one to three. Fruits orange-red specked with brown, globose with a pear-shaped base, 3⁄4 in. wide, persisting through the winter.
This fine thorn was said by Carrière (loc. cit.) to have originated in the Jardin des Plantes, Paris, from seed of C. mexicana (i.e. C. stipulacea). Certainly, it bears a strong resemblance to that species, which, however, has yellow fruit, not tapered where it joins the stalk, and its calyx-lobes are less conspicuously gland-toothed. The pollen parent is now generally thought to be C. crus-galli. It is one of the handsomest of all thorns, either in foliage, flower or fruit.
C. × grignonensis Mouillef. – Another hybrid from C. stipulacea, which it resembles more closely than does C. × lavallei. It was first observed at Grignon in France in 1873 and probably originated there. It has much the same garden value as C. × lavallei ‘Carrierei’, which it resembles in the long persistent leaves and fruits but from which it differs in its glabrous shoots.