Evergreen Blackberry
Rubus laciniatus
Washington State Classification
Class C — Widespread, County-Selected Control
It outcompetes native vegetation and prevents the establishment of native trees that require sun for germination.
Quick Reference
Identification
Growth Habit
It is an upright to rambling evergreen, perennial, woody shrub with stout stems that possess stiff, sharp, recurved prickles. It may grow up to 13 feet and stems can be about 30 feet long. Plants grow into impenetrable thickets.
Leaves
Leaves are alternately arranged and generally made up of 5 leaflets that are deeply divided and lobed with toothed margins. Leaves are green to dark green in color. Leaf undersides have hairs.
Flowers
Flowers are in clusters of 5 to 20. Each flower has 5 petals and 5 sepals. Petals are white to dark pink in color and are 3 lobed at the tips.
Fruit & Seeds
Mature fruit are shiny, black aggregate drupelets (blackberries). They are very tasty and ripen mid to late summer.
Impact
It outcompetes native vegetation and prevents the establishment of native trees that require sun for germination. It forms impenetrable thickets that block access to water and lacks the deep, bank stabilizing roots of native wetland shrubs and trees.
Ecology & Spread
Habitat
It grows in a wide range of conditions including disturbed areas, pastures, forest plantations, roadsides, riparian areas, riverbanks and wetland edges. Please click here to see a county level distribution map of evergreen blackberry in Washington.
Spread Mechanisms
Reproduction
Flowers can be self pollinated or be pollinated. It reproduces by seed and also vegetatively by sprouting root buds and root development on canes.
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Control Methods
Mechanical
- Hand pulling and grubbing out root balls is effective in controlling small infestations. Make sure to remove all roots as large roots left in the ground can re-sprout. Repeated mowing, several times a year over a number of years, can eventually kill the plant.
Cultural / Prevention
- Cultivation (rototilling or hoeing) will effectively eliminate plants. Mowing to prevent seed production is a very effective means of management. In lawns, mowing regularly at the proper height for the grass species may help minimize weed growth and invasion. Careful digging is useful to manage weed populations. However, digging can carry undesirable weed seed to the surface and foster further ger
Biological Control
- Long term grazing of goats can kill blackberry. Goats and pigs can control re-growth from 1 to 4 years old. Goats do tend to avoid mature canes. Chickens may decrease the seed banks.