Amelanchier cusickii |
Amelanchier fernaldii |
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Cusick's serviceberry, Cusick's shadbush, saskatoon |
amélanchier de Fernald, Fernald's shadbush |
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Habit | Shrubs, 2–8 m. Stems 1–50, solitary or in colonies. | Shrubs, 0.5–1 m, rhizomatous. |
Stems | 1–50, usually forming colonies. |
|
Leaves | fully unfolded; petiole (9–)12.8–19(–28) mm; blade elliptic to suborbiculate, (22–)33–46(–61) × (13–)25–32(–50) mm, base subcordate to truncate, each margin with (0 or)1–6(–11) teeth on proximal 1/2 and (2–)4 or 5(–7) teeth in distalmost cm, largest teeth 1 mm, apex usually truncate, sometimes mucronate to acute, abaxial surface glabrous or sparsely hairy by flowering, glabrous (or sparsely hairy) later, adaxial glabrous later. |
mostly or fully unfolded; petiole 1–25 mm; blade elliptic-oblong to oblong-obovate, 50–80 × 15–45 mm, base rounded to subcordate, each margin with 4–18 teeth on proximal 1/2 and 5–10 teeth in distalmost cm, largest teeth less than 1 mm, apex subacute to rounded or mucronate, abaxial surface glabrous (or sparsely hairy) by flowering, surfaces glabrous later. |
Inflorescences | (4–)6–8(–10)-flowered, (17–)26–36(–47) mm. |
3–8-flowered, 20–40 mm. |
Pedicels | (0 or)1 or 2 subtended by a leaf, proximalmost (4–)9–14(–18) mm. |
usually 1 subtended by a leaf, proximalmost 15–35 mm. |
Flowers | sepals erect to recurved after flowering, (2.6–)3.3–4.3(–5.3) mm; petals obovate to oblanceolate, (10.8–)13.3–20.1(–23.2) × (2.3–)3.3–6.3(–7.5) mm; stamens (14–)18–20(–21); styles (4 or)5, (1.7–)2.6–4(–4.8) mm; ovary apex glabrous or sparsely hairy (or with a ring of hairs at base of styles). |
sepals ascending or spreading after flowering, 3–5 mm; petals oval to broadly oblanceolate, 8–15 × 3–6 mm; stamens 20; styles 5, length unknown; ovary apex densely hairy. |
Pomes | bluish black, 10 mm diam. 2n = 4x. |
dark purple or almost black, 6–10 mm diam. |
Amelanchier cusickii |
Amelanchier fernaldii |
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Phenology | Flowering Mar–Jul; fruiting May–Aug. | Flowering Jun–Jul; fruiting Jul–Aug. |
Habitat | Basaltic ledges, cliffs, and bluffs along streams, stony soil, streambeds, stream banks, copses, mountainsides, roadsides | Ravines, thickets, barrens, rocky banks, shores, sea cliffs, swamps, wet woods, often calcareous |
Elevation | 600–2300 m (2000–7500 ft) | 0–100 m (0–300 ft) |
Distribution |
ID; MT; OR; WA; BC |
NB; NF; NS; PE; QC |
Discussion | Amelanchier cusickii has distinctively long petals. Leaves that are glabrous upon expanding and glabrous or sparsely hairy ovary apices are also useful for identification. The species flowers before A. alnifolia, which suggests that the two are genetically distinct. G. N. Jones (1946) noted that A. alnifolia and A. cusickii frequently grow together and that there is no evidence of hybridization; the authors have observed hybridization between A. alnifolia var. semiintegrifolia and A. cusickii. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The rhizomatous habit, leaves that are glabrous upon expanding, and densely hairy ovary apices in Amelanchier fernaldii are a distinctive combination of characteristics. Its relationships to congeners are unclear. Access to flowering material clearly assignable to A. fernaldii has not been available, and the size of floral parts was taken from M. L. Fernald (1950). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 652. | FNA vol. 9, p. 655. |
Parent taxa | Rosaceae > subfam. Amygdaloideae > tribe Maleae > Amelanchier | Rosaceae > subfam. Amygdaloideae > tribe Maleae > Amelanchier |
Sibling taxa | ||
Synonyms | A. alnifolia var. cusickii, A. basalticola | |
Name authority | Fernald: Erythea 7: 121. (1899) | Wiegand: Rhodora 22: 149. (1920) |
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