What’s a dichotomous key?
Help
Verbascum
See list of 6 species in this genusCollections of putative Verbascum lychnitis ×V. thapsus from Nantucket County, MA, require more study. The specimens— MacKeever N672 ( GH!) and MacKeever N822 ( NEBC!) appear referable to V. phlomoides. Reference: Ferguson (1972).
-
1a. Plants pubescent with simple, glandular hairs; filaments pubescent with purple, knob-tipped hairs; capsule subglobose, pubescent with minute hairs or glabrous
-
1b. Plants pubescent with compound, eglandular hairs; some of the filaments pubescent, usually the 3 upper (i.e., shorter) ones pubescent with white to yellow hairs and the 2 lower (i.e., longer) ones glabrous or nearly so (pubescent with purple hairs in V. nigrum); capsules ellipsoid to ovoid, densely pubescent
-
2a. Filaments pubescent with purple hairs; bracts 2–5 mm long; basal leaf blades cordate at base
-
2b. At least the upper 3 filaments pubescent with white to yellow hairs; bracts 8–40 mm long; basal leaf blades cuneate to rounded at the base
-
3a. Axis of inflorescence branched; calyx (1.5–) 2.5–4 mm long; anther reniform, not decurrent
-
3b. Axis of inflorescence unbranched (though a given plant may have more than 1 inflorescences); calyx 5–12 mm long; anther decurrent on the filament
-
4a. Stigma capitate; inflorescence crowded at maturity, the flowers concealing the axis of the spike; corolla 10–25 (–35) mm wide
-
4b. Stigma spatulate, decurrent on the sides of the style; inflorescence less dense at maturity, the flowers spaced enough to expose the axis of the spike [Fig. 908]; corolla (20–) 25–45 (–55) mm wide
-
5a. Leaves decurrent on the stem nearly or completely to the next leaf; floral bracts 15–40 mm long
-
5b. Leaves not, or only very shortly, decurrent on the stem; floral bracts 9–15 mm long
-
-
-
-
Show photos of:
Each photo represents one species in this genus.