Blackberry (Rubus species): Controlling an Invasive Weed

Wild blackberry can be a vexing weed almost anywhere in the U.S., but particularly troublesome in the Northeast, Southeast, and many Western areas. Roots are perennial but canes are biennial: they grow one year, then bloom and fruit the next. Plants spread rapidly by underground runners and seed.

To control, pull young plants in spring before they develop a perennial root system. To kill established clumps, repeatedly prune back stems as they sprout; this eventually exhausts roots. Or mow tops and dig out roots; repeat as new canes grow from roots left in soil.

For chemical control, cut stems to ground and apply glyphosate to stubs as soon as possible after cutting. Spot-treat new shoots with glyphosate as they appear. Or spray triclopyr or glyphosate on mature leaves, avoiding contact with desirable plants.