Sorbus rubescens McAll.

Sorbus rubescens is another species described from cultivation with quite a historic trail behind it. Its introduction is attributable to T.T. Yu’s collection (no. 13815) made near Zhongdian in 1937. A tree was grown at Wisley, from where seed was distributed; it returned to Ness from the Washington Park Arboretum, courtesy of the late Brian Mulligan (McAllister 2005a). It represents another apomict from the Zhongdian area, and may have S. filipes as one parent, contributing the pink flowers. The epithet rubescens indicates its tendency to flush red in some of the otherwise white fruits. It is a slow-growing, rather shrubby tree, but apparently reasonably tolerant of dry conditions. With its abundant crops of fruit it is horticulturally desirable, and is suitable for smaller gardens.

Sorbus filipes Hand.-Mazz. is probably a complex of similar apomictic taxa, found in the mountains of Yunnan east across southeastern Tibet to Bhutan and possibly Sikkim. They are characterised by their slender, shrubby habit and long narrow leaves with up to 17 pairs of leaflets. The flowers are deep pink or crimson and are followed by white or pink-flushed fruits (McAllister 2005a). Some occur only as shrubs, 1–2 m in height, with wand-like stems, but occasional tree forms are seen. To date, only apomictic tetraploids are known.