Amelanchier alnifolia var. pumila

Dwarf shadbush

Description
Shrubs.  Stems1–10, 1–3 m, single-stemmed or in small clumps; twigs glabrous at flowering.  Leaves conduplicate in bud; expanding or fully expanded and unfolded, green, glabrous or sparsely pilose abaxially by flowering; petioles 5–15 mm; blades abaxially pale green, suborbiculate to oval, 1–5 x 1–2 cm, somewhat coriaceous, bases cordate to truncate (somewhat cuneate), margins entire proximally, dentate in distal 1/2 with 3–5 teeth per cm, lateral veins 7–9 pairs, remaining distinct to the margin and not anastomosing, apices rounded or subtruncate, surfaces glabrous.  Inflorescences 4–8-flowered, erect or ascending, 2–4 cm, only proximalmost pedicel subtended by leaf.  Pedicels glabrous, proximalmost 0.6–1.2 cm.  Flowers: hypanthia campanulate, 3–4 mm diam.; sepals recurving after flowering, 3 mm, glabrous adaxially; petals white, oblanceolate, 8–12 x 3–4 mm, not andropetalous; stamens 12–15; styles 4–5; ovary summit rounded, glabrous. Pomes dark purple, glaucous, 8–9 mm diam., sweet.

Flowering/Fruiting
Flowering May–Jun; fruiting Jul–Sep.

Habitat
Mountain slopes, plains; 1600–3400 m

Range
Calif., Colo., Idaho, Mont., Oreg., Utah, Wyo.

Discussion
The most distinctive feature of Amelanchier pumila is that its leaves, pedicels, sepals, and ovary summits are glabrous at all times (with the exception of a few hairs on emerging leaves in some plants).