Sorbaria (Ser.) A.Braun
(D.R.G., W.R.S.)
Deciduous, usually suckering, large shrubs, not armed; stems ± erect, glabrate. Lvs distributed along young stems, large, imparipinnate; leaflets toothed, petiolulate; stipules small, free, persistent. Infl. a large terminal panicle of many small fls. Fls 5-merous, ⚥, small, shortly pedicellate. Hypanthium broadly cup-shaped. Epicalyx 0. Sepals persistent; lobes reflexed. Petals ovate to suborbicular, small but exceeding calyx, white. Stamens 20-50, inserted at mouth of calyx tube. Ovary superior; carpels (4)-5-(8), fused at base; styles 5; ovules several. Fr. of usually 5 follicles; seeds several in each follicle, small.
c. 10 spp., C. and E. Asia, N. America. Naturalised sp. 1.
Superficially Sorbaria spp. resemble some Spiraea spp. and the genus was once included in Spiraea. However, no Spiraea sp. has compound lvs. In their vegetative parts Sorbaria spp. superficially resemble some spp. of Sorbus sect. Sorbus, but the latter do not form suckering thickets and in addition differ very markedly in their infl. and fr.
