There has been considerable confusion between this species, Prunus incisa, and Prunus apetala - all three being distinguished by having black fruits and a leaf with a long tail-like apex and a conspicuous double toothing. This species is distinct enough in other respects from Prunus apetala, a cherry very downy or hairy in many of its parts. Prunus incisa is also more or less downy on the young shoots, leaf-stalk and calyx, the leaves are smaller, the branchlets never become bright brown as in Prunus nipponica, and the flowers are normally smaller[
The taxonomic history of Prunus is long and complicated, in part due to the economic value of its fruit crops and also the ease with which some species hybridize. Here, Prunus is circumscribed in its broad sense based on the argument that when viewed on a worldwide scale, the morphologic discontinuities among the segregate genera diminish and they overlap with one another. Included here are species that have at times been placed in the genera Amygdalus, Armeniaca, Cerasus, Laurocerasus, Padus, and Persica.
At the species level, Prunus has been the object of the usual combining and splitting common among taxonomists with different philosophies and opinions. In particular, over-reliance on the indument of various vegetative and floral parts has led to the naming of numerous species and infraspecific taxa. Similarly, too much has been made of fruit colour and palatability in naming taxa of Prunus. It is very likely that, as molecular and genetic data are analyzed and, more importantly, correlated with morphological data, circumscriptions will be redrawn and the number of Prunus species will be reduced[
Cerasus nipponica (Matsum.) Nedol.
Common Name: Japanese Alpine Cherry
Prunus nipponica is a deciduous shrub usually growing 2.5 - 5 metres tall, occasionally becoming a bushy-headed tree up to 6 metres[
The plant is harvested from the wild for local use as a food. It is often grown as an ornamental in gardens.
There is currently insufficient information available to evaluate this species. The plant is classified as 'Data Deficient' in the IUCN Red List of Threatened Species(2013)[
The plant (especially the seed and young shoots) contains cyanogenic glycosides, especially amygdalin and prunasin. When injested, these compounds break down in the digestive tract to release cyanide. Used in small quantities in both traditional and conventional medicine, this exceedingly poisonous compound has been shown to stimulate respiration, improve digestion, and promote a sense of well-being[
]. It is also claimed by some to be of benefit in the treatment of cancer - though this claim has been largely refuted.
In larger concentrations, however, cyanide can cause gasping, weakness, excitement, pupil dilation, spasms, convulsions, coma and respiratory failure leading to death[
The fruits and flowers of most members of this genus generally have low or very low concentrations of this toxin, though the seeds and young shoots can contain much higher levels.
The levels of toxin can be detected by the level of bitterness:- for example sweet tasting almond seeds are a major food crop and are often eaten in quantity, whilst bitter tasting almond seeds are used as a flavouring (in marzipan for example) but are not usually eaten on their own.
In general, it can be considered safe to eat any fruit or seed from species in this genus that either have a sweet flavour or are slightly bitter. Great caution should be taken, however, if the flavour is moderately to very bitter[
E. Asia - Russian Far East, central and northern Japan.
High elevations in the mountains[
|Other Uses Rating
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[
]. Succeeds in sun or partial shade though it fruits better in a sunny position[
Some named forms have been developed for their ornamental value[
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[
Fruit - raw or cooked. Small[
], The black, globose fruit is about 8mm 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.
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[
A green dye can be obtained from the leaves[
A dark grey to green dye can be obtained from the fruit[
The plant is a secondary genetic relative of Sweet Cherry (Prunus avium) so it has the potential for use as a gene donor for crop improvement, particularly in providing disease resistance[
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, mid summer in a frame[
Softwood cuttings from strongly growing plants in spring to early summer in a frame[
Layering in spring.