Pacific Plum, Klamath plum, Kellogg's Klamath plum, Oregon Klamath plum
Prunus subcordata
Family: Rosaceae
What it is like
Prunus subcordata is a deciduous Tree growing to 7.5 m (24ft 7in). See above for USDA hardiness. It is hardy to UK zone 7. It is in flower in April, and the seeds ripen from August to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers moist soil.
Height (m): 7.5
Where it is found
By streams, on dry hillsides and in open pine forests.
South-western N. America - Oregon to California.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 3
Fruit - raw or cooked in pies, preserves etc. Pleasantly acid, the best forms have a slight astringency that imparts a distinctive flavour to culinary products made from the fruit. Considered to be one of the best flavoured wild fruits of Pacific N. America. The fruit is up to 3cm in diameter and contains one large seed. Seed - raw or cooked. Do not eat the seed if it is too bitter - see the notes above on toxicity.
Seed: includes nuts, cereals, peas and beans.
Medicine
Rating: 1
Although no specific mention has been seen for this species, all members of the genus contain amygdalin and prunasin, substances which break down in water to form hydrocyanic acid (cyanide or prussic acid). In small amounts this exceedingly poisonous compound stimulates respiration, improves digestion and gives a sense of well-being.
Other
Rating: 2
A green dye can be obtained from the leaves. A dark grey to green dye can be obtained from the fruit. Wood - heavy, hard, close grained. The trees are too small for the wood to be of commercial interest.
Dye: Plants that provide dyes.
Wood: A list of the trees and shrubs that are noted for having useful wood.
How it is grown
Thrives in a well-drained moisture-retentive loamy soil, growing well on limestone. Prefers some lime in the soil but is likely to become chlorotic if too much lime is present. Requires a sunny position. Occasionally cultivated for its edible fruit, there are some named varieties. Most members of this genus are shallow-rooted and will produce suckers if the roots are damaged. Plants in this genus are notably susceptible to honey fungus.
Propagating it: Seed - requires 2 - 3 months cold stratification and is best sown in a cold frame as soon as it is ripe. Sow stored seed in a cold frame as early in the year as possible. Protect the seed from mice etc. The seed can be rather slow, sometimes taking 18 months to germinate. Prick out the seedlings into individual pots when they are large enough to handle. Grow them on in a greenhouse or cold frame for their first winter and plant them out in late spring or early summer of the following year. Cuttings of half-ripe wood with a heel, July/August in a frame. Softwood cuttings from strongly growing plants in spring to early summer in a frame. Layering in spring.
Best place to grow: Woodland Garden Secondary; Sunny Edge;
Habit: Tree
Hardiness: 6-9
Growth:
Soil: Light (sandy), medium, heavy (clay)
Shade: No shade
Moisture: Moist
Things to keep in mind
Although no specific mention has been seen for this species, it belongs to a genus where most, if not all members of the genus produce hydrogen cyanide, a poison that gives almonds their characteristic flavour. This toxin is found mainly in the leaves and seed and is readily detected by its bitter taste. It is usually present in too small a quantity to do any harm but any very bitter seed or fruit should not be eaten. In small quantities, hydrogen cyanide has been shown to stimulate respiration and improve digestion, it is also claimed to be of benefit in the treatment of cancer. In excess, however, it can cause respiratory failure and even death.