Project Description



Crown Gall on Ilex

A bacteria caused infection that causes large, corky galls up to several inches in diameter to appear at the base of the plant and on the stems and roots. The galls are rounded, with a rough, irregular surface. Plants with numerous galls are weak, growth is slowed and leaves turn yellow. Branches may die back. The galls disrupt the flow of water and nutrients to the top of the plant. The bacteria are spread by infested soil, transplants and contaminated tools. Even though infected plants cannot be cured, they usually survive for many years. To improve the appearance of the plant, prune out and destroy affected stems below the galled area. Sterilize pruning shears after each cut with rubbing alcohol. Destroy severely infected shrubs. No spray or soil treatments are effective.