baceous, without thorns
=Dwarf Raspberry, Rubus triflorus.=

18a. Leaves thin, dull above; fruit black, large and juicy
=Dewberry, Rubus villosus.=

18b. Leaves firm or thick, shining above; fruit reddish, small,
consisting of a few sour drupelets
=Swamp Dewberry, Rubus hispidus.=

19a. Ripe fruit dropping away from the white receptacle or core;
terminal leaflet of each leaf with a long stalk, while the lateral
leaflets are sessile or nearly so (Raspberry) --20.

19b. Ripe fruit and receptacle or core dropping together; all the
leaflets on stalks which are approximately equal in length
(Blackberry) --22.

20a. Stem very glaucous with a whitish or bluish waxy deposit;
fruit black =Black Raspberry, Rubus occidentalis.=

20b. Stem not glaucous; fruit red --21.

21a. Calyx velvety-pubescent =Red Raspberry, Rubus idaeus.=

21b. Calyx bristly-hispid
=Red Raspberry, Rubus idaeus var. aculeatissimus.=

22a. Pedicels with gland-tipped hairs, but no prickles
=Blackberry, Rubus allegheniensis.=

22b. Pedicels with prickles =Blackberry, Rubus nigricans.=

22c. Pedicels with neither prickles nor gland-tipped hairs --23.

23a. Leaves downy beneath =Blackberry, Rubus frondosus.=

23b. Leaves smooth beneath =Blackberry, Rubus canadensis.=

24a. Ovaries 1 or more, superior (attached to the surface of the
receptacle, but not concealed within it or united to it) --25.

24b. Ovary 1, inferior (permanently enclosed within the receptacle,
with only the styles protruding) --38.

25a. Ovaries more than 1 --26.

25b. Ovary 1 --30.

26a. Leaves serrate --27.

26b. Leaves lobed --28.

27a. Leaves glabrous or very nearly so (8-20 dm. high; flowers white or
pinkish, summer) =Meadow-sweet, Spiraea salicifolia.=

27b. Leaves closely pubescent beneath (5-15 dm. high; flowers pink,
summer) =Hardhack, Spiraea tomentosa.=

28a. Flowers showy, purple or white, 3-4 cm. broad --29.

28b. Flowers white, about 1 cm. wide (1-3 m. high; flowers in early
summer) =Ninebark, Physocarpus opulifolius