Flora of North America species comparison

4-16 dm, densely to sparingly prickly.

4-12(-18) dm, moderately prickly throughout, prickles patent, longest 7-10 mm.

blades: surfaces copiously prickly on veins and intervein surfaces to sparingly prickly on main veins only;

basal lobed ca. 1/2 distance to midrib, lobe apices usually distinctly rounded, marginal teeth usually less than 1 mm;

distal usually definitely clasping.

blades: abaxial surface prickly on main veins, adaxial surface unarmed or sparingly prickly on midrib;

basal blades shallowly to often deeply lobed;

distal not clasping.

buds oblong to ellipsoid to obovoid, body 12-22 × 10-16 mm, prickly;

sepal horns terete, flattened or angular in cross section, (4-)6-8(-10) mm, unarmed to densely prickly.

buds subglobose to oblong, body 15-18 × 12-15 mm, sparingly prickly, prickles patent;

sepal horns usually slender, terete, (5-)8-12(-14) mm, unarmed or with 1-2 prickles near base.

5-10(-13) cm broad, not closely subtended by foliaceous bracts;

petals white;

stamens 150-250;

filaments pale yellow;

pistil 3-5-carpellate.

6-9 cm broad;

petals white;

stamens about 150;

filaments pale yellow;

pistil 3-4-carpellate.

ovoid, ellipsoid, or lanceoloid, 35-55 × 9-15(-18) mm (including stigma and excluding prickles), prickly, longest prickles to 10 mm, widely spaced, or shorter, more numerous, and interspersed with still shorter prickles, surface then partially obscured.

narrowly ellipsoid to narrowly ellipsoid-ovoid, 30-45 × 8-14 mm (including stigma and excluding prickles), scattered-prickly, surface clearly visible, longest prickles 6-8(-10) mm.

1.8-2.6 mm.

to 2 mm.

= 28.