Trees, 20–100(–150) dm. Stems 5–30 cm diam.; bark dark gray or gray-brown, scaly; young branches dark brown or reddish brown, densely tomentose, becoming glabrous; flowering shoots becoming spurs, 40–150 mm. Buds dark red or purple, ovoid, 3–4(–5) mm, scale margins densely puberulous. Leaves convolute in bud; isomorphic; stipules deciduous, lanceolate, 3–5 mm, apex acuminate; petiole 10–35 mm, tomentose to sparsely pubescent; blade elliptic, ovate, or broadly elliptic, (2–)5–10 × (1–)3–6.5 cm, base broadly cuneate or rounded, margins unlobed, obtusely serrate, sometimes serrate-crenate, apex acute, abaxial surface glabrescent, adaxial densely puberulent. Panicles umbel-like; peduncles absent; bracteoles deciduous, filiform, 5–7 mm. Pedicels 10–25 mm, puberulous. Flowers 30–40 mm diam.; hypanthium tomentose; sepals reflexed at flowering, triangular-lanceolate or triangular-ovate, 6–8 mm, equal to or longer than tube, apex acuminate, surfaces tomentose; petals (rose in bud) white, sometimes pink, obovate, 15–25 mm, claws 1 mm, margins entire, apex rounded; stamens 20, 9–10 mm, anthers yellow before dehiscence; styles 5, basally connate less than 1/2 length, 9–10 mm, slightly longer than stamens, basally gray-tomentose; stigmas green. Pomes green, yellow, or red, pure, striped, or blushed, globose or depressed-globose, 20–50(–70) mm diam., skin with bloom or wax, sometimes russetted or dotted, cores enclosed at apex; sepals persistent, erect; sclereids absent. Seeds light brown. 2n = 34 (51, 68).
Phenology: Flowering Apr–May; fruiting Jul–Oct.
Habitat: Abandoned or naturalized in thickets, forests, fields, fence edges, shores, roadsides
Elevation: 0–1600 m
Introduced; St. Pierre and Miquelon, B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., P.E.I., Que., Ala., Alaska, Ark., Calif., Colo., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Oreg., Pa., R.I., S.C., Tenn., Utah, Vt., Va., Wash., W.Va., Wis., Wyo., c Asia, introduced also in Mexico, Central America (El Salvador, Guatemala), South America (Argentina), Europe, e Asia, Africa (South Africa), Pacific Islands (New Zealand, Tristan da Cunha), Australia.
Malus pumila is cultivated for its edible apple. Historically, the nomenclature of the orchard apple has been confusing, with many species names applied to cultivar groups. Based on extensive nomenclatural research, D. J. Mabberley et al. (2001) concluded that M. pumila is the correct binomial for the species of central Asia that is ancestral to orchard apples. Commonly used binomials, such as M. domestica Borkhausen (an illegitimate name), M. paradisiaca (Linnaeus) Medikus, and M. sylvestris, have been placed in synonymy. Quian G. Z. et al. (2010) have proposed to conserve M. domestica and reject M. pumila. Their proposal is still under consideration by the Nomenclature Committee for Vascular Plants.
Some trees, although originally planted, may appear naturalized when found in old, overgrown areas. Naturalized trees are derived from seeds distributed by birds and mammals and from apples discarded by people. Trees grown from seeds often produce small, bitter, and sour fruit.