Flora of North America species comparison

blades pale green or glaucous abaxially, slightly darker pale green adaxially, ovate to elliptic, rarely obovate, 25–39 × 16–20 mm, margins entire to obscurely serrate, abaxial surface glabrous, eglandular (sometimes hairy or glandular along midvein), adaxial surface usually glabrous (sometimes hairy and/or glandular).

deciduous;

blade dark to pale green or glaucous, elliptic to narrowly elliptic, 15–41 × (5–)6–16(–20) mm, margins usually sharply, uniformly serrate (serrations sometimes minute, tipped with stipitate gland), surfaces glabrous or hairy, especially along abaxial midvein, eglandular abaxially.

calyx pale green or glaucous, lobes vestigial or absent, glabrous;

corolla pink, bronze-pink, or greenish white, globose, sometimes urceolate, 5–7 × 4–5 mm, thin, glaucous;

filaments glabrous or pilose basally.

calyx green, glaucous, glabrous;

corolla usually white, cylindric to urceolate, 4–6 mm;

filaments ciliate; (tubules with introrse, elongate pores).

blue, dull purplish black, or black, sometimes glaucous, 8–10 mm diam.

black or blue, rarely white, 3–12 mm diam., glabrous.

ca. 1 mm.

(3–)10–15(–20), ca. 1.2 mm.

= 24, 48.

= 48.