Black berries are indeed hard to kill. Some areas in Washington state and Oregon have gone to pasturing goats in these areas. Goats naturally will eat the berry bushes first over grass. By keeping the leaves stripped off the plant and eating the new growth they eventually starve the plant to death. This has happened on my own property when I moved my goats into a pasture with wild roses, russian thisthle, mint, knap weed and cat tails. 3 years later I have a pasture that is primarily grass and clover, the stream is no longer chocked with cat tails and best of all, happy goats.
By
11/01/2010
Look for a broad leaf weed killer that is labeled safe for lawns. Most of the phenoxy herbicides (2,4-D, dicamba, MCPA, etc.) will do minimal damage to grasses and take care of the broad leaf weeds just fine. Blackberries will be very hard to kill - many repeated applications of the weed killer will be needed!