× Sorbaronia alpina (Willd.) Schneid.

A deciduous shrub whose young shoots are at first covered with loose white down, becoming dark with age. Leaves oval to obovate, tapering equally to both ends or more abruptly to the apex, finely toothed, 11⁄2 to 3 in. long, about half as wide, at first soft and covered beneath with pale down; stalk 1⁄4 to 1⁄2 in. long. Flowers in terminal corymbs 1 to 2 in. across, white, opening in May; styles three or four. Fruits ovoid to obovoid, dark brownish-red, 1⁄3 in. wide.

A hybrid between Sorbus aria and Aronia arbutifolia. It is very nearly allied to × S. dippelii but differs in having red fruits and in the leaves (upper surface especially) being less downy. Var. superaria Zab. is apparently a reversion towards Sorbus aria or perhaps a cross between that species and × S. alpina; the leaves are much larger and broader than in the latter, the flower clusters are also larger, the fruits deep red.

This shrub has been known in gardens since early in the 19th century.

There is an example at Kew measuring 30 × 31⁄2 ft (1971).