My Avondale Redbud Tree Has Yellow Leaves

Identification

• Redbud trees are susceptible to verticillium wilt, which is caused by Verticillium spp. The fungus persists for extended periods in soil. The pathogen infects trees through the roots and starts to damage the vascular system.

Damage

• Infection of the vascular system leads to poor distribution of water and nutrients. Initial signs include fading, yellowing and browning foliage, often occurring in scattered areas first before spreading throughout the tree. This is followed by branch and shoot dieback. Inspection of sapwood or the wood under the bark reveals dark stains. The entire tree eventually dies.

Control

• Preventative measures are among the best management practices. Maintain tree health with adequate fertilizer and irrigation. Prune and remove affected tree areas. Plant new trees in well-drained soil. The University of California Extension recommends soil solarization before planting.