Flora of North America species comparison

4-10(-15) dm, sparingly to moderately prickly.

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

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

basal and proximal lobed 1/2-4/5 distance to midrib;

distal 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 broadly ellipsoid to subglobose, body 12-18 × 10-16 mm, sparingly to rather closely prickly;

sepal horns terete, 3-6(-10) mm, usually unarmed.

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 cm broad, closely to more distantly subtended by 1-2 foliaceous bracts;

petals white;

stamens 150 or more;

filaments lemon yellow;

pistil (3-)4-5(-7)-carpellate.

6-9 cm broad;

petals white;

stamens about 150;

filaments pale yellow;

pistil 3-4-carpellate.

oblong, oblong-ellipsoid, or narrowly ellipsoid, 20-40(-45) × 10-15(-25) mm (including stigma and excluding prickles), prickly, surface clearly visible to partially obscured, longest prickles widely spaced, 6-10(-12) mm, sometimes interspersed with smaller ones.

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.

1.6-2 mm.

to 2 mm.

= 28.