Tip Blight
Diaporthe vaccinii or Diplodia tip blight agents
61 host plants
Last updated
Tip blight affects new growth tips on spruce, pine, and arborvitae in Western Washington, causing browning or dieback of shoot terminals. Affected tips may show discoloration starting at the very tip and progressing toward the base, eventually killing the current season's growth. The problem is most visible in spring and early summer once new growth is fully expanded.
The key to managing tip blight is identifying the specific causal agent affecting your trees, since different pathogens require different management approaches. Prune out affected tips to reduce disease spread and improve appearance, but focus on maintaining tree vigor and proper site selection. Avoid planting susceptible species in locations prone to late spring frosts, wind damage, or poor air circulation.