Shrub or small tree to 3 m. Branchlets red and hairy when young, glabrous later. Buds dark red, ovoid; scales hairy at margin. Leaf blade broadly ovate, 4–8 × 3–7 cm, sparsely hairy above, densely hairy on veins beneath when young; base cordate; apex acuminate or acute ; margin doubly toothed, usually 3-lobed, sometimes deeply; petiole 1–3 cm. Inflorescence a 6–8-flowered corymb, 4–6 cm across; pedicels ~2 cm, villous. Flowers 3.5 cm diameter, in late spring (May in the wild). Sepals triangular-lanceolate, 2–3 mm, tomentose above, falling before fruit ripe; petals white, obovate, about 1.8 cm; stamens 20–30, about half the length of the petals; styles 3–4, slightly exceeding the stamens. Fruit red, September in the wild, ellipsoid, 1–1.5 × 0.8–1 cm, with few stone cells. (Gu et al. 2003).
Distribution China S Jilin (Changbai Shan) North Korea
Habitat Among shrubs; 1100–1300 m asl.
USDA Hardiness Zone 3-7
RHS Hardiness Rating H6
Conservation status Endangered (EN)
Perhaps the rarest wild apple species, and virtually unknown in western cultivation, Malus komarovii is one of the small-fruited East Asian species whose calyx falls away before the fruit is ripe. It can be distinguished from M. kansuensis by its cordate leaf base and larger flowers with shorter sepals on shorter pedicels. It tolerates very cold winters (Gu et al. 2003).
This tree was first described from mossy valley woods in modern North Korea, by Komarov from his own specimens, although his name Crataegus tenuifolia proved invalid (Komarov 1901; Rehder 1920). Most known sites are in North Korea, but its range extends across the Chinese border into the Changbai Mountains. It is threatened by habitat fragmentation and loss, although it is afforded some inadvertant protection in the Demilitarized Zone (IUCN 2020).
Ernest Wilson collected three specimens from shrubby examples in Korea during August and September 1917 (Rehder 1920). At least one (W 9177) was in fruit, so it is possible that a seed collection was also made. An old record of Crataegus tenuifolia at the Arnold Arboretum, without further details, suggests that it might once have grown there (Arnold Arboretum 2020).
The only record of this species currently being grown in our area is at the US National Clonal Germplasm Repository, Geneva, NY (USDA/ARS, National Genetic Resources Program 2020). The Eden Project, Cornwall, is attempting to introduce M. komarovii as part of a Korean planting made in conjunction with the Korea National Arboretum (Eden Project 2019).