Amelanchier alnifolia

Saskatoon serviceberry

Rosaceae

The Basics

Taxonomy: Kingdom - Plantae (plants). Subkingdom - Tracheobionta (vascular plants). Superdivision - Spermatophyta (seed plants). Division - Magnoliophyta (flowering plants). Class - Magnoliopsida. Subclass - Rosidae. Order - Rosales. Family - Rosaceae (rose). Genus - Amelanchier Medik. Species - Amelanchier alnifolia (Nutt.) Nutt. ex M. Roem.

Ecology: Saskatoon serviceberry is common in lower-elevation coniferous forests. It also occurs in montane chaparral, mountain shrub, and the upper limits of pinyon-juniper (Pinus-Juniperus spp.) communities. In plains grasslands it mostly occurs in wooded draws, grassland-woodland interfaces, and riparian zones. Saskatoon serviceberry is common in riparian areas throughout its distribution. Riparian associates in the Northern Rocky Mountains include white alder (Alnus rhombifolia), hawthorn (Crataegus douglasii), chokecherry (Prunus virginiana), bitter cherry (P. emarginata), Greene mountain-ash, and elderberry (Sambucus spp.). Saskatoon serviceberry rarely establishes from seed in early stages of primary succession. Saskatoon serviceberry is common after disturbances such as fire, logging, or insect outbreak. It may persist in the understory for decades, but eventually dies out with canopy closure. Where available in quantity, Saskatoon serviceberry is often a primary or important component of the winter diet of big game species. Saskatoon serviceberry is planted as an ornamental and to produce commercial fruit crops.

Identification

Shrubs, 1–12 m. Stems 1–50, solitary or colonial. Leaves 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. Inflorescences (4–)6–11(–16)-flowered, (8–)14–43(–62) mm. Pedicels: (0 or)1 or 2(or 3) subtended by a leaf, proximalmost (2–)3–20(–29) mm. Flowers: 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). Pomes black or purple, 8–15 mm diam.

Threats

Fire effects: Saskatoon serviceberry sprouts from the root crown and/or rhizomes after fire. After light- to moderate-severity fire, it usually sprouts from the root crown or from shallowly buried rhizomes. However, deeply buried rhizomes enable Saskatoon serviceberry to sprout after even the most intense wildfire.

Reproduction

Flowering and Fruiting - Regeneration from seed is apparently rare, being limited by moisture, low spring temperature, and/or disease. Flowers are produced almost every year, but because of drought, spring frost, and/or juniper rust (Gymnosporangium spp.), good seed crops may be produced only every 3 to 5 years. Even under good conditions, most fruits contain some unviable seed. Seed is dispersed by frugivorous birds and mammals. It is dormant and requires overwinter stratification.

Vegetative Reproduction - Vegetative reproduction by sprouting from the root crown and rhizomes are most common.

Species Distribution

Citation

USDA Plants Database
USDA, NRCS. 2016. The PLANTS Database. National Plant Data Team, Greensboro, NC 27401-4901 USA.

USFS Plant Database
Habeck, R. J. 1992. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.

Flora of North America
Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 19+ vols. New York and Oxford.

The Jepson Herbarium
The Jepson Manual: Vascular Plants of California. B.G. Baldwin, D.H. Goldman, D.J. Keil, R. Patterson, T.J. Rosatti, and D.H. Wilken [editors]. 2012. 2nd edition, thoroughly revised and expanded. University of California Press, Berkeley, CA.

USGS Plant Species Range Maps
Critchfield, W.B., and Little, E.L., Jr., 1966, Geographic distribution of the pines of the world: U.S. Department of Agriculture Miscellaneous Publication 991, p. 1-97. Little, E.L., Jr., 1971-1978, Atlas of United States trees, volume 1,3,13,17, conifers and important hardwoods: U.S. Department of Agriculture Miscellaneous Publications.