Amelanchier alnifolia
Amelanchier intermedia
alder-leaf shadbush, amélanchier à feuilles d'aulne, saskatoon, saskatoon berry, saskatoon serviceberry, service berry, western serviceberry
amélanchier intermédiaire, intermediate serviceberry, intermediate shadbush
mostly unfolded;
petiole (3–)6.8–19.1(–28) mm;
blade usually elliptic to oval to suborbiculate, sometimes quadrangular, (14–)24–47(–67) × (7–)17–36(–55) mm, base usually subcordate to truncate, sometimes ± tapering or ± cuneate, each margin with 0–3(–9) teeth on proximal 1/2 and (0–)3–5(–8) teeth in distalmost cm, largest teeth more than 1 mm, apex rounded to truncate or occasionally acute or mucronate, abaxial surface sparsely to densely hairy (or glabrous) by flowering, sparsely to moderately hairy (or glabrous) later, adaxial glabrous or sparsely (moderately) hairy later.
half-unfolded;
petiole (14–)16–21.8(–24) mm;
blade elliptic to slightly obovate, (39–)46–65(–77) × (25–)26–38(–45) mm, base subcordate or rounded, each margin with (5–)13–19(–20) teeth on proximal 1/2 and (5–)13–19(–20) teeth in distalmost cm, largest teeth less than 1 mm, apex acute to short-acuminate, abaxial surface sparsely hairy by flowering, surfaces glabrous later.
(4–)6–11(–16)-flowered, (8–)14–43(–62) mm.
(6 or)7–10-flowered, 35–59(–77) mm.
(0 or)1 or 2(or 3) subtended by a leaf, proximalmost (2–)3–20(–29) mm.
0 or 1 subtended by a leaf, proximalmost (13–)14–25(–33) mm.
sepals erect to recurved after flowering, (1.4–)2.2–4(–4.9) mm;
petals oblanceolate to oval or obovate to elliptic, (5.7–)9.5–14(–18.8) × (2.2–)3.3–5.2(–6.6) mm;
stamens (10–)15–21(–22);
styles (3 or)4 or 5(or 6), (1.3–)2–2.9(–3.9) mm;
ovary apex moderately to densely hairy (or glabrous).
sepals ascending to recurved after flowering, (2–)3.3–4.5(–5.2) mm;
petals oblong, (10–)12.7–17.7(–18.5) × (3–)3.9–5.3(–5.7) mm;
stamens (18–)20(–21);
styles (4 or)5, (3.3–)3.8–4.8(–5) mm;
ovary apex glabrous (or sparsely hairy).
black or purple, 8–15 mm diam.
dark purple, 7–12 mm diam. 2n = 4x.
Amelanchier alnifolia
Amelanchier intermedia
Varieties 3 (3 in the flora).
Amelanchier alnifolia is widespread and polymorphic, and its taxonomic and geographic limits have been viewed differently. L. Cinq-Mars (1971) considered this species to range eastward to the Gaspé Peninsula. Disagreements about the boundary between A. alnifolia and A. humilis are evident in herbarium specimen annotations. The distinctness of the varieties of A. alnifolia has also been questioned. G. N. Jones (1946) treated the three varieties recognized here as distinct species and noted that the leaves of var. alnifolia and var. semiintegrifolia (A. florida) are virtually indistinguishable, and, although petal lengths of the two do not overlap, occasional larger-flowered var. alnifolia and occasional smaller-flowered var. semiintegrifolia occur, so the petal length distinction is not an absolute one. Geographically these two varieties are largely separate, with var. alnifolia occurring in the Great Plains and Rocky Mountains and var. semiintegrifolia on the Pacific slopes of mountains from Alaska to northern California.
Amelanchier alnifolia is thought to hybridize with Sorbus scopulina (x\Amelasorbus jackii Rehder).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Amelanchier intermedia is morphologically closest to A. laevis. In a study of morphologic variation involving A. canadensis, A. intermedia, A. laevis, and other species of Amelanchier, A. C. Dibble et al. (1998) found that the only two species that overlap are A. intermedia and A. laevis. P. Landry (1975) considered A. intermedia to be the hybrid of A. arborea (including A. laevis) and A. canadensis, and the authors have data that suggest A. intermedia is a hybrid of A. canadensis and A. laevis.
Amelanchier intermedia hybridizes with A. bartramiana, A. humilis, and A. spicata (L. Cinq-Mars 1971).
A. C. Dibble et al. (1998) reported that two individuals of Amelanchier intermedia, both tetraploids, were apomictic.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Ovary apices glabrous (or sparsely hairy); shrubs 1–2(–4) m. | var. pumila |
1. Ovary apices moderately to densely hairy (or glabrous); shrubs or trees, 1–12 m | → 2 |
2. Inflorescences (8–)26–43(–62) mm; proximalmost pedicels (5–)8–16(–29) mm. | var. alnifolia |
2. Inflorescences (8–)14–26(–35) mm; proximalmost pedicels (2 or)3–8(–13) mm. | var. semiintegrifolia |
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
KS Wildflowers, 
MN Wildflowers, 
PNW Herbaria, 
SW CO Wildflowers, Turner Photog. 
WildflowerSearch
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USDA Plants Database- LBJ Wildflower Center
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