Fig. 205. Rhamnus alnifolia.
Leaf-scars alternate or sometimes nearly opposite, small, crescent-shaped or half-elliptical; bundle-traces 3 or joined in a series; stipule-scars minute.
Although the common name, Buckthorn is applied to species of this genus, many of them are not thorny.
b. Twigs red or brown, glabrous
b. Twigs gray, often downy
1. R. alnifolia L'Her. Alder-leaf Buckthorn. Low spreading shrub, 1. 5-8 dm. high, with slender unarmed upright gray branches and smooth bark; twigs red or brown, glabrate; buds small, under 5 mm. long; leaf-scars alternate. Swamps and meadows, Newfoundland to British Columbia, south to West Virginia, Illinois, Nebraska, Wyoming and California (Fig. 205).
2. R. lanceolata Pursh. Lanceleaf Buckthorn. Erect shrub up to 2 m. high, with slender unarmed branches and smooth grayish bark; twigs reddish-brown, often downy; buds small, 5 mm. or less long. Thickets, Alabama to Texas, north to Pennsylvania and Nebraska (Fig. 206).
3. R. caroliniana Walt. Carolina Buckthorn. Indian Cherry. Shrub or small tree up to 11 m. high, without thorns; young branch-lets puberulent; buds short, scarcely 5 mm. long; fruiting pedicels several in a cluster. Rich woods,Florida to Texas, north to Virginia, Missouri, and Nebraska (Fig. 207).
Fig. 206. Rhamnus lanceolate.
Fig. 207. Rhamnus caroliniana.