Crataegus douglasii aka Black Hawthorn

Crataegus douglasii, or black hawthorn, belongs to the rose family. This North American plant grows across a broad native range. Reports place it from Alaska to Quebec and south into California. Its range also reaches Nevada, South Dakota, and Michigan. It grows most often in the Pacific Northwest. Wild plants grow beside streams, in meadows, and on slopes. They also grow in wetlands and open woods.

It forms a small tree or a dense, spreading shrub. Garden trees often reach 20–30 feet [6.1–9.1 metres] tall. Their crowns can spread to 25 feet [7.6 metres]. Some reports give heights of 40 feet [12.2 metres]. Shrub forms may stand just 10 feet [3 metres] tall. Root suckers let plants spread into thickets over time. Young twigs are red, then turn gray as they age. Sharp thorns reach about one inch long. Thin, dark gray bark splits into narrow scales with age. The simple green leaves grow in an alternate pattern. They have an oval or wedge shape and toothed edges. The plant sheds its leaves each year.

White flowers open in May and June in flat-topped corymbs. Each small flower has five petals and a cup-shaped base. Their smell can turn unpleasant as the flowers age. Midges visit the flowers and help pollinate them. Round fruits turn from red to black by late summer. Their sweet, juicy flesh surrounds up to five large seeds. People eat the fruit fresh, cooked, or dried. It also goes into pies and preserves. Fallen fruit can make a mess in autumn. Some fruit stays on the tree after it shrivels.

Full sun gives the best fruit crop, though partial shade works. Moist soil suits it, but established plants also withstand drought. It accepts clay, loam, and sand across a broad pH range. Sources give differing cold limits, with the broadest spanning USDA zones 3–9. Prune in late winter when growth needs control. Seed-grown plants may need five to eight years to fruit.

Use it as a lawn tree, screen, hedge, or streamside planting. Its roots help hold soil, and its branches shelter nesting birds. Flowers supply nectar, while leaves feed several butterfly larvae. Its hard, heavy wood has served as material for tool handles. Rusts, fire blight, scab, mildew, leaf spots, and cankers can occur. Borers, caterpillars, lace bugs, leaf miners, and scale also attack it. ASPCA lists it as non-toxic to cats, dogs, and horses. Its thorns still pose a physical hazard.