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: Strawberry-Raspberry

General Information

Rubus illecebrosus is a perennial plant, woody at the base, producing each year a cluster of erect to arching, prickly, annual stems from a woody rootstock; the stems are generally 50 - 100cm tall, occasionally reaching 150cm[]. The plant spreads by means of its creeping, underground stems, and can form large clusters of growth[].
The plant is commonly harvested from the wild for local use as a food. It is occasionally cultivated as a fruit crop, especially in the USA and Russia, and is also sometimes grown as an ornamental in gardens, where it can be used as a ground cover[].
Plants spread freely when in a suitable site and are apt to become invasive[]. They have escaped from cultivation and become established in various countries[, , ].

Known Hazards

None known

Botanical References

, ,

Range

E. Asia - Japan (Honshu, Kyushu, Shikoku)

Habitat

Thickets and waste ground[].

Properties

Weed Potential	Yes
Edibility Rating
Other Uses Rating
Habit	Deciduous Shrub
Height	0.60 m
Pollinators	Insects
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Easily grown in a good well-drained loamy soil in sun or semi-shade[, , ].
Sometimes cultivated for its edible fruit and occasionally naturalized in Europe[].
The plant adopts an almost herbaceous habit and is botanically a sub-shrub, only a small amount of woody stem persists overwinter[].
Plants in this genus are notably susceptible to honey fungus[].
Rubus illecebrosus is distinguished from other raspberries by its prickly, glabrous, eglandular stems, pinnately compound leaves with typically seven lanceolate to narrowly ovate leaflets, relatively large flowers, white petals, and 50 - 100 drupelets[].

Edible Uses

Fruit - raw or cooked. Fairly large and sweet but insipid raw[, ]. The fruit is said to develop more flavour when it is cooked[]. Another report says that the fruit is sour, bitter and unpalatable raw[, ], though this does not agree with the plants we are growing[]. The red, oblong fruit can be 14 - 30mm in diameter[, , ].

Medicinal

None known

Agroforestry Uses:

A good ground cover plant for a sunny position or light shade[]. It spreads freely once established, but dies down over the winter and thus can allow other species to invade[].

Other Uses

This species is sometimes used in breeding programmes with the raspberry (Rubus idaeus) in order to increase yields.[]

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.
Division in early spring or just before leaf-fall in the autumn[].