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| 1 Stems strongly white-glaucous; fruits with 1-5 (-20) drupelets, glaucous |
| 1 Stems not glaucous (or with a slight 'bloom' when young); fruits with (5-) 10-50 drupelets, not glaucous. |
| ..2 Stems primarily armed with narrow-based prickles or even narrower bristles, with or without stout-based prickles as well. |
| ....3 Inflorescence racemiform; bristles of the stem nonglandular (very small glandular hairs may be present) |
....3 Inflorescence reduced, normally to a single flower per branch of the floricane |
| ..2 Stems armed with stout-based, usually recurved prickles (bristles lacking, though weak, stalked glands may be present); leaf undersurfaces nearly glabrous or softly pubescent; leaves deciduous. |
| ......4 Leaf undersurface thinly hairy, not soft to the touch (when fully developed). |
| ........5 Canes 4-7 mm in diameter, 4-12 dm tall |
| ........5 Canes up to 5 mm in diameter, 2-6 dm tall. |
| ..........6 Primocane leaves with prominent venation, leaflets typically plicate, flowers on pedicels < 4 cm long, the inflorescence compact |
| ..........6 Primocane leaves with inconspicuous venation, flowers on pedicels often exceeding 4 cm. |
| ............ 7 Primocane leaves with 3 leaflets; inflorescences with 1 (-3) flowers, 5-8 cm long |
| ............ 7 Primocane leaves with 3-5 leaflets; inflorescences with 1-12 flowers, 5-20 cm long. |
| ............ ..8 Canes 2-3 mm in diameter; prickles 1-2 mm long; primocane leaves mostly with 3 leaflets; inflorescences with 1-6 flowers |
| ............ ..8 Canes 3-5+ mm in diameter; prickles 2-4 mm long; primocane leaves mostly with 5 leaflets; inflorescences with 4-12 flowers. |
| ............ ....9 Primocanes with 1-3 prickles per cm of length; tips of central primocane leaflets gradually or relatively long-tapered to the tip |
| ............ ....9 Primocanes with 3-5 prickles per cm of length; tips of central primocane leaflets abruptly tapered to the tip |
| ......4 Leaf undersurface densely hairy, soft to the touch. |
| ............ ......10 Inflorescence axes with stalked glands (use 10× magnification). |
| ............ ........11 Primocane terminal leaflets elliptic, the base cuneate to rounded; inflorescences with 1-2 flowers |
| ............ ........11 Primocane terminal leaflets ovate to elliptic, the base cordate to subcordate; inflorescences often with > 2 flowers. |
| ............ ..........12 Primocanes with 3-5 prickles per cm of length, primocane terminal leaflets coarsely serrate, ≤ 7 cm long and 4.5 cm wide, ovate to elliptic |
| ............ ..........12 Primocanes with 1-3 prickles per cm of length, primocane terminal leaflets finely serrate, ≥ 7 cm long and 4.5 cm wide, mostly ovate |
| ............ ......10 Inflorescence axes lacking stalked glands. |
| ............ ............ 13 Canes 4-7 mm in diameter, 4-12 dm in height; inflorescences mostly racemose, with 4-8 flowers |
| ............ ............ 13 Canes mostly 2.5-5 mm in diameter, 2-6 dm in height; inflorescences not racemose, with flowers clustered near the tip, with 1-7 (-8) flowers. |
| ............ ............ ..14 Flowers on pedicels < 3.5 cm long, the inflorescence compact |
| ............ ............ ..14 Flowers on pedicels (at least some of them) > 3.5 cm long, some of the pedicels conspicuously ascending. |
| ............ ............ ....15 Primocane terminal leaflets with coarsely incised margins; inflorescences usually with just 1 flower; sepals often with an obviously spatulate tip 1-3 mm long |
| ............ ............ ....15 Primocane terminal leaflets regularly toothed; inflorescences usually with 2-8 flowers; sepals tapered to a sharply pointed tip. |
| ............ ............ ......16 Primocane terminal leaflets elliptic, rounded at the base |
| ............ ............ ......16 Primocane terminal leaflets ovate, cordate at the base |