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[].

Common Name: Rocky Mountain Chokecherry

General Information

Prunus virginiana melanocarpa is a deciduous shrub that can grow up to 360cm tall.
The plant is harvested from the wild for local use as a food, medicine and source of materials. It is sometimes cultivated as a fruit crop.

Known Hazards

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[].

Botanical References

, ,

Range

Western N. America - N. Dakota to British Columbia, south to California and New Mexico.

Habitat

Prairies and valleys[]. Moist soils along creeks in valleys and on hills and mountainsides; at elevations up to about 2,500 metres[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Shrub
Height	3.60 m
Pollinators	Insects
Cultivation Status	Wild

Cultivation Details

Requires a well-drained moisture retentive soil[]. Requires a sunny position[]. Thrives in a loamy soil, doing well on limestone[]. Prefers some chalk in the soil but apt to become chlorotic if too much is present[].
Occasionally cultivated for its edible fruit in N. America, and sold in local markets, there is at least one named variety[].
The fruit is not very freely borne in Britain[].
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[].

Edible Uses

Fruit - raw or cooked[]. The fruit must be fully ripe otherwise it is very astringent[]. The fruit of this sub-species is larger and less astringent than Prunus virginiana and some forms can be quite nice raw[]. A cherry-like flavour[], it can also be dried and is then quite nice raw[]. The fruit can also be made into syrup, jams, jellies etc[]. The native N. American peoples ground the fruit, seeds and all, into a paste and dried them into cakes which were later soaked in water, mixed with flour and sugar and used as a sauce[]. The black, globose fruit is around 6 - 14mm in diameter; it contains a single large seed[, , ].

Seed - raw or cooked[]. Do not eat the seed if it is too bitter - see the notes above on toxicity.

The bark and twigs are a tea substitute[, ].

Medicinal

The bark is astringent, pectoral, sedative and tonic[, ]. The bark can be made into a cough syrup[].

A drink of the fruit juice has been used to stop bleeding following the delivery of a baby[].

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[].

Agroforestry Uses:

The plant forms thickets by means of suckers from its extensive root system and can be planted for erosion control[].

Other Uses

A green dye can be obtained from the leaves[].
A green dye is obtained from the inner bark in spring[]. A red-brown dye can be obtained from the inner bark[].
A dark grey to green dye can be obtained from the fruit[]. A dark red dye can be made from the fruit[].
A purplish-red dye is obtained from the fruit[].

The wood is close grained, moderately strong, hard, heavy. Too small to be of commercial interest, but it is used for skewers etc[, ].
The wood does not burn easily[, ]

Propagation

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.
Division of suckers during the dormant season. They can be planted out direct into their permanent positions.