Cypress Canker on Italian Cypress: Identification and Management

Not a Beetle—It’s a Fungal Canker

When only a few trees in a row show dying branches while others stay healthy, the cause is usually cypress canker (a spore-borne fungus), not insects. The fungus enters through natural or pruning wounds during cool, wet periods.

Symptoms

• Foliage yellows near the infection site; unaffected areas stay green.
• Cankers girdle branches, cutting off water flow.
• Progressive dieback can kill the entire tree.

Prevention Is Critical (No Cure Exists)

• Plant in full sun with well-drained, porous soil.
• Apply a moderate mulch layer to keep soil cool and moist.
• Avoid planting where other cypresses have died—spores persist in soil for years.

Slowing the Spread

• Prune infected branches with tools sterilized between cuts.
• Fungicidal sprays may suppress the fungus but will not eradicate it.

Early detection and strict sanitation offer the best chance to prolong tree life.