[6][7][8][9][10][11][5][12][13] The two species share many similarities, and probably recently diverged from a common ancestor, leading to differences in taxonomic interpretation, particularly regarding the more intermediate eastern Asian plants.

The most distinctive physical difference among these plants is usual presence of gland-tipped hairs on first-year canes, petioles, pedicels, and calyces of R. strigosus, lacking in R. idaeus.

Some authors also treat various raspberries in eastern Asia, east from the Altai Mountain Range in Mongolia to Manchuria and Japan in this taxon (where it is suggested to have originated along with a great deal of the North American flora),[7] but others include all Asian raspberries in R.

In its first year, a new stem grows vigorously to its full height of 0.5–2 m, unbranched, and bearing large pinnate leaves with three or five (rarely seven) leaflets; normally it does not produce any flowers.

In its second year, the stem does not grow taller, but produces several side shoots, which bear smaller leaves with three leaflets.