Rhamnus alnifolia

Shrubs, 0.5–1(–1.5) m, unarmed. Branchlets gray to brown, glabrous or pubescent. Leaves deciduous, alternate; petiole 5–15 mm; blade dark green to olive green on both surfaces, lanceolate-oblong to elliptic or lanceolate-ovate, 4.5–11 cm, herbaceous, base cuneate to rounded, truncate, or subcordate, margins crenate to crenate-serrate, apex obtuse to acute or acuminate, abaxial surface glabrous or puberulent along veins, adaxial surface glabrous or glabrate; secondary veins (4–)5–7 pairs, all diverging at nearly same angle. Inflorescences fascicles or flowers solitary. Pedicels 2–10 mm. Sepals 5. Petals 0. Drupes black, globose or slightly elongate, 6–8 mm; stones 3.

Phenology: Flowering May–Jul.
Habitat: Fens and swamps, generally calcareous, riparian thickets, interdunal swales, shore lines, marshes and mats, wet meadow edges, outcrops, deciduous and coniferous forests.
Elevation: 10–2700 m.

Alta., B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., P.E.I., Que., Sask., Calif., Conn., Idaho, Ill., Ind., Iowa, Maine, Md., Mass., Mich., Minn., Mont., N.H., N.J., N.Y., N.Dak., Ohio, Oreg., Pa., R.I., S.Dak., Tenn., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.

Discussion

Rhamnus alnifolia is a primary host for the soybean aphid.

Selected References

None.

Lower Taxa