Prunus subcordata aka Klamath Plum

Prunus subcordata is a deciduous plum in the rose family. Its common names include Klamath plum, Sierra plum, and Pacific plum. Its native range runs from Oregon into California. Oregon records place it in the state's southern counties. These include Klamath and Lake counties, where it is most frequent. It also grows in California's Coast Range and Sierra Nevada. There, its range reaches about 6,000 feet [1,800 metres] above sea level.

This plant forms a shrub or small tree with thickets. It can reach about 25 feet [7.5 metres] in height. A short trunk supports crooked branches that extend sideways. The thin bark has a gray-brown tone. As it ages, cracks and small, scaly plates develop. Slender, smooth twigs become dark red-brown with clear lenticels. Older twigs bear short spur shoots that can look like thorns. These traits give the branches a rougher look with age.

The leaves grow in an alternate pattern along the twigs. Each leaf is simple, with a broad egg-shaped or oval outline. Leaves measure about one to three inches long. Their tips and bases can both have rounded shapes. The edges have teeth, sometimes with smaller teeth within them. The upper face is smooth, glossy, and dark green. The lower face has a paler shade of green. Small yellow-green glands occur near the leaf base or stalk. The name subcordata refers to an almost heart-shaped outline.

Small flowers grow in loose groups on slender stalks. Each bloom has five rounded petals, first white, then pink. Flowers measure about half an inch across. Each flower has both male and female parts. The fruit is an oblong drupe with one large stone. Ripe fruit may be yellow, deep red, or purple. The flesh is sour but edible. A ridge runs along one side of the stone.

For cultivation, Oregon State recommends sun and soil that drains well. The plant accepts a range of soils but grows best with moisture. That source places its cold hardiness at USDA Zone 7. Its flowers, fruit, and thicket form provide its main garden features. The supplied accounts do not identify specific pests or diseases. They confirm edible flesh but do not establish other parts as safe.