A deciduous shrub up to 10 or 15 ft high, closely allied to R. periclymenoides and joined to it by intermediates. It differs chiefly in the densely downy winter-buds and young branchlets, the corollas glandular as well as hairy outside, and the soft, appressed hairs on the ovary (in R. periclymenoides they tend to be bristly). The leaves are usually grey-downy beneath, especially on the midrib and veins, and it is then distinguishable from R. periclymenoides by that character alone; f. subglabrum Rehd., however, has the leaves almost glabrous beneath, but does not otherwise differ from typical R. canescens and should not be confused with R. periclymenoides.
Native of the eastern USA, mainly in the coastal plains of the south-east but reaching as far north as N. Carolina and west to Tennessee. According to Loudon it was introduced in 1810, but has been much confused with R. periclymenoides.