Shrub or rarely small tree to 5-6 m tall. Leaves elliptic-ovate, about 7 cm long with 3-7 large teeth on each margin or sometimes lobed, hairy below, stalked. Flowers in clusters about 20 cm long; summer.

H. dumosus (Nutt.) Heller, Rock Spiraea, also from W North America, is similar but the leaves have simple teeth and a minute stalk.

W North America.

Source: Spencer, R. (2002). Rosaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 3. Flowering plants. Dicotyledons. Part 2. The identification of garden and cultivated plants. University of New South Wales Press.