Amelanchier interior
Amelanchier canadensis
amélanchier de l'intérieur, inland serviceberry, Wiegand's shadbush
amélanchier du Canada, Canada serviceberry, Canadian serviceberry, eastern shadbush
not fully unfolded;
petiole 10–30 mm;
blade broadly ovate to elliptic, 30–70 × 20–50 mm, base rounded to subcordate, each margin with 3–15 teeth on proximal 1/2 and (2–)4 or 5(–7) teeth in distalmost cm, largest teeth less than 1 mm, apex short acuminate to apiculate, abaxial surface glabrous or sparsely hairy by flowering, surfaces glabrous later.
less than half-unfolded;
petiole (5–)10–15(–25) mm;
blade elliptic or oval to oblong or obovate, (24–)34–48(–67) × (12–)18–27(–42) mm, base subcordate, rounded, or cuneate, each margin with (0–)6–15(–29) teeth on proximal 1/2 and (0–)6–12(–17) teeth in distalmost cm, largest teeth less than 1 mm, apex subacute or obtuse to rounded and mucronate, abaxial surface densely hairy by flowering, glabrous or sparsely to moderately hairy later, adaxial glabrous or sparsely (moderately) hairy later.
4–12-flowered, 30–75 mm.
(3–)7–10(–15)-flowered, (6–)15–37(–74) mm.
1 or 2 subtended by a leaf, proximalmost 10–45 mm.
0 or 1(or 2) subtended by a leaf, proximalmost (1–)5–14(–17) mm.
sepals recurved after flowering, 2–5 mm;
petals obovate, 6–15 × 4–5 mm;
stamens 20;
styles 5, 3–5 mm;
ovary apex densely (moderately) hairy (or glabrous).
sepals erect, ascending, or spreading after flowering, (0.3–)1.8–3.1(–4.6) mm;
petals linear, elliptic, or oblong, (4–)6–10.2(–15) × (1.8–)2.6–4(–5.3) mm;
stamens (15–)19–21(–28);
styles (3–)5(or 6), (1.5–)3.4–4.7(–5.8) mm;
ovary apex glabrous (or moderately hairy).
purple-black, 6–8 mm diam. 2n = 4x.
purplish black or maroon-purple, 6–10 mm diam.
Amelanchier interior
Amelanchier canadensis
Amelanchier interior is distinguished by its capacity to grow into a tree to ten meters and by having sparsely hairy young leaves that are often reddish and densely hairy ovary apices. E. L. Nielsen (1939) differentiated A. interior and A. wiegandii on the basis of leaves being carinate in A. wiegandii as opposed to flat in A. interior, and leaf sinuses rounded versus acute. G. N. Jones (1946) considered those differences to be slight, and he included A. wiegandii in A. interior. The authors follow Jones, but retain the common name Wiegand’s shadbush to commemorate Wiegand’s early insights about the taxonomy of Amelanchier. M. L. Fernald (1950) considered A. wiegandii as suggesting a small-leaved A. laevis but with shorter buds, fewer teeth, fewer veins, and summit of ovary heavily tomentose. P. Landry (1975) thought A. wiegandii to be the hybrid of A. arborea and A. sanguinea, and E. G. Voss (1972–1996, vol. 2) reasoned that A. interior is a hybrid swarm involving A. laevis (or sometimes A. arborea) and plants of the A. spicata and/or A. sanguinea complex. A hybrid origin of A. interior from A. laevis and A. sanguinea is reasonable given that stem height, the number of leaf teeth, and petal length are more or less intermediate between those two species. DNA sequences from ITS region indicate that A. interior (A. wiegandii) is a possible later-generation hybrid involving a member of the western North American ITS clade (which also includes A. humilis and A. sanguinea of eastern North America) and some eastern North American taxon (C. S. Campbell et al. 1997). Multiple hybrid origins, possibly from different species, may explain the variability of A. interior. Amelanchier interior has unusually large ranges of lengths for proximal pedicels, sepals, and petals. The leaves of A. wiegandii were described by Nielsen as bronze at flowering; Jones described the leaves of A. interior as green when young. The authors assume that A. interior as they interpret it is polymorphic for the color of young leaves.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Varieties 2 (2 in the flora).
The type specimen of Amelanchier canadensis, from Virginia or Canada, includes a single stem with five leaves and the remnants of an infructescence with three fruits. Much of the difficulty in determining the identities of specimens and species distributions owes to the limited diagnostic value of the type. The authors include A. obovalis as a variety of A. canadensis because of ecologic and morphologic similarities. W. W. Ashe (1903) described A. obovalis as a shrub of swamps and loose soils, 9–15 dm or a tree to 4 m with inflorescences 3–5 cm and proximalmost pedicels 3–9 mm at flowering and 20–30 mm in fruit. K. M. Wiegand (1912) described A. canadensis (as A. oblongifolia) as a shrub with slender, erect stems in dense fastigiate colonies with inflorescences 25–60 mm, the proximalmost pedicels 8–18 mm and scarcely longer in fruit. Wiegand was uncertain about placement of specimens of A. obovalis from the southeastern United States and stated that they appeared to be this species. The circumscription by Wiegand of A. oblongifolia and the circumscription by Ashe of A. obovalis overlap considerably. The two species co-occur in similar habitats, have overlapping phenologies, and individual populations may contain specimens with intermediate morphologic characters, especially at early successional sites. Experimental crosses between plants representing the morphologic and ecologic extremes result in formation of mature fruit and seed (C. T. Frye, unpubl.). Plants growing among rocky outcrops in the Potomac River Gorge in Maryland and Virginia suggest A. spicata in growth form and habitat but differ in having glabrous ovary apices and the finely toothed leaves of A. canadensis. These plants are also unusual in that most individuals in the population rarely produce fruits suggesting the presence of locally dominant self-incompatibility allele(s).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Petals (4–)7–10.2(–15) mm; inflorescences (12–)21–37(–74) mm; proximalmost pedicels (6–)8–14(–17) mm; shrubs 0.5–8 m; stems in open to dense colonies. | var. canadensis |
1. Petals (5–)6–8(–10.4) mm; inflorescences (6–)15–27(–45) mm; proximalmost pedicels (1–)5–10(–15) mm; shrubs 0.2–2 m; stems in dense colonies, often evidently stoloniferous. | var. obovalis |
IL Wildflowers
MI Flora
MN Wildflowers
WildflowerSearch
iNaturalist
USDA Plants Database
Go Botany
MD Biodiversity
