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: Oregon Cut-Leaf Blackberry

General Information

Rubus laciniatus is an evergreen to tardily deciduous shrub producing a cluster of erect to arching (sometimes creeping), very spiny, biennial stems growing from a woody rootstock - the stems can be 200cm or more long[]. 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. Plants in the wild can form dense thickets.
The plant is commonly harvested from the wild for local use as a food. It has been cultivated as a fruit crop since the late 17th century and is probably the most important and widely cultivated domesticated blackberry in the world. It is grown on a large scale, mainly in the form of the spineless chimera-mutation 'Thornless Ever-Green'. The plant is also often cultivated for ornament and as a ground cover[].
The plant has great potential as a weed - it frequently occurrs as a garden escape and regionally it is fully naturalized in Central and W Europe (e.g. Great Britain, Denmark, Germany, Poland, USA)[, ].

Known Hazards

None known

Botanical References

, ,

Range

Widely cultivated as a food crop, the origin of this plant is uncertain.

Habitat

Not known in a truly wild situation, the plant has become established along woodland edges, semiopen woods, rocky and/or moist soil, open areas, often disturbed, roadsides; at elevations up to 1,800 metres through much of N. America[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Semi-deciduous Shrub
Height	2.00 m
Growth Rate	Fast
Pollinators	Insects, Apomictic
Self-fertile	Yes
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Easily grown in a good well-drained loamy soil in sun or semi-shade[, , ].
The plant produces apomictic flowers, these produce fruit and viable seed without fertilization, each seedling is a genetic copy of the parent[].
Sometimes cultivated for its edible fruit, it is a very vigorous and productive plant[]. There are several named varieties. including 'Oregon Cutleaf Thornless' which is high yielding with good flavoured fruits and no prickles on the stems, thus making it easier to harvest[].
Although top growth is killed by fire, the plant usually resprouts very vigorously from the rootstock[].
Plants in this genus are notably susceptible to honey fungus[].
Rubus laciniatus is the only blackberry in the flora area that has leaflets so deeply lobed and dissected or has 3-lobed petals. Rare individuals bearing relatively unlobed leaflets and perianth parts may be part of the natural variation of this species or be hybrids with some other species. Putative natural hybrids have been reported with Rubus bifrons (as Rubus procerus; R. K. Bammi and H. P. Olmo 1966). Such unusual plants of Rubus laciniatus would be distinguished from the native blackberries by their thyrsiform and notably stipitate-glandular inflorescences and evergreen to late-deciduous leaves[].
Although widely introduced in the flora area, Rubus laciniatus is a less aggressive weed than Rubus bifrons[].

Edible Uses

Fruit - raw or cooked[, , , ]. Large sweet and juicy with a fine flavour[, ]. The black, globose to subcylindrical fruit is about 10 - 20mm in diameter[, ].

Medicinal

The fruit, roots, and stems have been used to make various medicinal preparations[]. No more details are given, but some of the most common medicinal uses of Rubus species is based around their content of tannins and other polyphenols, which make them astringent and antiinflammatory[].

Agroforestry Uses:

The plant is sometimes grown as a ground cover[].
Most, if not all, thicket-forming species of Rubus have good erosion control value. They usually grow satisfactorily on barren and infertile soils and invade and occupy eroded areas. They also establish quickly on burns, old fields, and logged areas. Forming extensive and nearly impenetrable thickets, they can provide excellent cover for wildlife as well as nesting sites for small birds. They are often natural pioneer species, paving the way for woodlands to develop, but they should only really be used within their native range in order to avoid any risks of them invading other habitats[, ].

Other Uses

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[].