Galls Round, rough-surfaced overgrowths near soil line or graft of plants are crown galls. They are often caused by a bacterium. Control by using disease-free stock. Avoid plant injuries. Cut galls and infected branches, then burn them. Cedar-apple galls appear on junipers as orange tentacles attached to a brown ball. The disease does little harm to junipers but causes a rust on apple trees. The results: deformed fruit and leaf loss. To prevent, don't grow junipers near apple trees.