The genus Rubus, (especially the blackberries, which are often loosely referred to as Rubus fruticosus agg.) presents some of the most difficult taxonomic problems. This is partly due to the frequency of polyploidy; also to the frequent occurrence of hybridization; and also due to apomixis, where minor differences between plants are preserved because seedlings are genetically identical to their parent. As a result, differences of opinion on the number of species to be recognized from a given region can vary tremendously (for example, a treatment by M. L. Fernald[] in 1950 recognized 205 species for the northern half of the eastern United States plus parts of southeastern Canada, whilst H. A. Gleason and A. Cronquist in 1991 recognized only 25)[]. Where possible, a relatively conservative approach is taken here[].

Common Name: Black Raspberry

General Information

Rubus occidentalis is a deciduous shrub producing a cluster of erect to arching, prickly, biennial stems from a woody rootstock; the plant can grow 50 - 250cm tall[] The stems only produce leaves, and do not flower, in their first year of growth; forming flowering branches in their second year and then dying after fruiting.
The plant is harvested from the wild for local use as a food and sometimes also as a medicine. It is often cultivated as a fruit crop In Canada and the USA, occasionally also in Europe[], and is sometimes grown as an ornamental[].

Known Hazards

None known

Botanical References

, ,

Range

Eastern and Central N. America - Ontario to Quebec and New Brunswick, south to Colorado, Mississippi and Georgia

Habitat

Rich thickets, ravines and borders of woods[], often in full shade[] and preferring moist positions[]. Woodlands, fields, prairies, meadows, savannahs, in disturbed areas, dry to moist soil; at elevations up to 1,000 metres[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Shrub
Height	3.00 m
Pollinators	Insects
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Easily grown in a good well-drained loamy soil in sun or semi-shade[, , ]. Plants can tolerate deep shade, though do not fruit well in such a position.
This species is sometimes cultivated, especially in N. America, for its edible fruit[], it is a parent of many named varieties[, ].
Plants in this genus are notably susceptible to honey fungus[].
Rubus occidentalis is the source of most of the black raspberries in cultivation[].

Edible Uses

Fruit - raw or cooked and used in pies, preserves etc[, , , , , , ]. Aromatic[]. It is of variable quality, with the finest forms having a rich acid flavour[]. The usually dark purplish to black, rarely amber, hemispherical fruit is about 15mm in diameter[, ].

Young shoots - raw or cooked like rhubarb[, , , ]. They are harvested as they emerge through the soil in the spring, and whilst they are still tender, and then peeled[].

A tea is made from the leaves and another from the bark of the root[, ], 257.

Medicinal

The roots are cathartic[]. A decoction of the roots has been used in the treatment of gonorrhoea[]. The root has been chewed in the treatment of coughs and toothache[]. The root has been used, combined with Hypericum spp, to treat the first stages of consumption[].
An infusion of the roots has been used as a wash for sore eyes[].

An infusion of the astringent root bark is used in the treatment of diarrhoea and dysentery[, ].

The leaves are highly astringent[]. A decoction is used in the treatment of bowel complaints[].
A tea made from the leaves is used as a wash for old and foul sores, ulcers and boils[, ].

A decoction of the roots, stems and leaves has been used in the treatment of whooping cough[].

Other Uses

The plant is used in breeding programmes with the raspberry (Rubus idaeus) - it has been used to impart resistance to spur-blight disease of the leaves.
Crossing of Rubus idaeus × Rubus occidentalis have produced very fruitful hybrids, which are usually called Rubus × neglectus Peck[]

A purple to dull blue dye is obtained from the fruit[].

Propagation

Seed - requires stratification and is best sown in early autumn in a cold frame. Stored seed requires one month stratification at about 3°c and is best sown as early as possible in the year. Prick out the seedlings when they are large enough to handle and grow on in a cold frame. Plant them out into their permanent positions in late spring of the following year.
Cuttings of half-ripe wood, mid summer in a frame[].
Tip layering in July. Plant out in autumn.
Division in early spring or just before leaf-fall in the autumn[].