Common Blackberry

Ecological Considerations:

Rubus allegheniensis, commonly called Common Blackberry, is a native woody shrub that forms canes that are initially erect, but often bend downward to re-root in the ground. These canes actively grow and form leaves during the first year, and develop fruits in the form of drupes during the second year, after which they die down. The canes are about 3-6′ tall; they are green where there is new growth at the tips, otherwise they are brown or reddish brown with stout prickles that are straight or somewhat curved. The alternate leaves are usually trifoliate or palmately compound; they have long petioles. The leaflets are up to 4″ long and 3″ across; they are up to twice as long as wide. A typical leaflet is usually ovate with coarse, doubly serrate margins; it may have a few scattered white hairs on the upper surface, while the lower surface is light green and pubescent.

The canes develop racemes with about 12 white flowers; these racemes are much longer than they are wide. There are conspicuous glandular-tipped hairs on the peduncles and pedicels of the inflorescence. A flower has 5 white petals and 5 green sepals with pointed tips; this flower is about ¾-1″ across. The petals are longer than the sepals, rather rounded, and often wrinkly. In the center of each flower, are numerous stamens with yellow anthers surrounding a green reproductive structure with a prickly appearance. The flowers bloom during late spring or early summer for a month; there is little or no floral fragrance. The drupes develop later in the summer; they are about ¾” long and 1/3″ across, although their size varies with moisture levels. The drupes are initially white or green, but eventually turn red, finally becoming almost black. They are seedy and have a sweet flavor when fully ripened. The root system consists of a taproot. This plant often forms loose colonies vegetatively.

Map areas where this plant can be used for revegetation:

Propagation Mechanisms/Strategies for Encouraging its Establishment:

Best Planting Practices/Options and Pros and Cons of Options:

Common Blackberry preference is for light shade to full sun, and mesic conditions. Some drought is tolerated, although this can reduce the size of the drupes. Growth is best in rich fertile soil; a clay-loam or rocky soil is also acceptable. This plant is easy to grow from transplants or cuttings of young growth. It can become aggressive and be difficult to eliminate.

Key Issues Regarding its Ecology:

Associated Ecological Benefits:

The nectar and pollen of the plant’s flowers attract many kinds of insects including bees, wasps, flies, butterflies, and beetles. Caterpillars and moths feed on the Common Blackberry. Birds, and mammals feed on the fruit, stems, or foliage of this plant and help to distribute the seeds far and wide. The Common Blackberry provides some shelter and shrubby protection to various ground-nesting birds and small mammals. In general, the ecological value of blackberries is very high.

Availability of Locally Sourced Seeds and Plants:

Case Studies of Native Plant Establishment Efforts/Lessons Learned:

Additional photos:

Sources cited:

Search at Rhode Island Native Plant Guide
Illinois Widflowers

Key Words:

Native
Shrub
Rubus allegheniensis
Common Blackberry