OregonFlora species comparison

opposite, narrowly oblong to ovate or subcordate, 30–150 × 5–30 mm, bases clasping;

margins entire;

tips acute;

surfaces glabrous.

cauline, alternate (upper leaves sometimes whorled) or occasionally opposite, 1–15 cm;

surfaces usually glabrous, petiolate or sessile;

stipules 0 or greatly reduced.

involucres bell-shaped, 2.5–4 mm;

glands 2-horned; horns rounded and short.

multiple individual flowers grouped into a cyathium of 5 groups of 5–many staminate flowers around a pistillate flower;

involucres usually with 4–5 prominent glands;

glands often with horn-like projections.

sepals 0;

petals 0.

;

stamens 1.

1; central;

styles fused at base.

spherical, 5–15 mm.

round, 4–6 mm, wrinkled or with shallow reticulate markings.