What's eating my monterey cypress?

Monterey Cypress is most seriously threatened by cypress bark canker (Seiridium cardinale) that spreads via bark-feeding insects and wounds. Aphids, bark beetles, and cypress tip moth also cause damage. Deer may browse young specimens. Avoid wounding bark when pruning and remove canker-infected branches promptly.

Resin-soaked cankers on bark; foliage on affected branches turns yellow then red-brown; progressive crown dieback; dark sunken lesions beneath bark Prune out infected branches well below cankers, sterilizing tools between cuts; dispose of infected material; no effective fungicide — prevention via tree vigor is key

Small bore holes in bark with resin tubes; galleries under bark disrupt vascular tissue; associated with bark canker spread; branch dieback Maintain tree health; remove dead and dying wood promptly; avoid unnecessary pruning wounds in summer; pyrethroid trunk sprays for high-value trees

Dense colonies on shoots; sticky honeydew leads to sooty mold; yellowing and wilting of young shoot tips; ant tending of colonies Spray with insecticidal soap or neem oil targeting colonies; encourage parasitic wasps and ladybirds; strong water jets dislodge early infestations