Shepherdia
Gen. N. Amer. Pl. 2: 240. 1818. name conserved
Taxon | Illustrator ⠉ | |
---|---|---|
Elaeagnus commutata Shepherdia canadensis Hippophaë rhamnoides |
Shrubs or trees, dioecious, armed or unarmed, clonal or not. Stems densely pubescent with brown or silver scales and stellate hairs or glabrescent. Leaves deciduous or evergreen, opposite; short-petiolate; blade elliptic, ovate, obovate, or subcordate, base attenuate or blunt, apex acute or blunt, surfaces sparsely pubescent or with silvery and rust scales and stellate hairs. Inflorescences usually umbellate, flowers rarely solitary, usually appearing after leaves (before in S. argentea). Pedicels absent. Flowers unisexual; hypanthium conspicuous elongated; calyx lobes 4; nectary disc conspicuous or inconspicuous; stamens 8, alternate and opposite calyx lobes; style linear, stigmatic on 1 side. Fruits berrylike, red, red-orange, yellow, or green, fleshy or dry. Seeds smooth. x = 11, 13.
Distribution
North America
Discussion
Species 3 (3 in the flora).
Shepherdia was considered part of Elaeagnus by A. Nelson (1935); it is easily distinguished by its opposite leaves and sessile, unisexual flowers. Species of Shepherdia are tolerant of alkaline soils and extremes of temperature. The first two species described here have been grown in arboreta; M. A. Dirr (2009) stated that neither is horticulturally attractive. The third species (S. rotundifolia) has horticultural potential for water-efficient landscapes in arid parts of the western United States.
Selected References
None.
Key
1 | Leaf blade surfaces bicolored, sparsely silvery-pubescent abaxially, with stellate hairs interspersed with rust-brown scales, glabrate and green adaxially. | Shepherdia canadensis |
1 | Leaf blade surfaces not bicolored, silvery pubescent and without rust-brown scales. | > 2 |
2 | Leaves deciduous, blades elliptic or obovate, margins plane; plants clonal. | Shepherdia argentea |
2 | Leaves evergreen, blades broadly ovate, margins revolute; plants not clonal. | Shepherdia rotundifolia |