Plant Diagnostics

Nectria canker - Nectria (Neonectria)

Damage

Nectria canker is characterized by the production of sore-like wounds (cankers) that form on twigs, branches, and trunks. Cankers can form at leaf scars and wherever injuries occur. Injuries can be caused by pruning (particularly improper pruning), frost, hail, cracking from heavy snow or ice, sunscald, insects, or mammals. Cankers appear first as slightly sunken areas on the bark, but can grow for years, becoming target-shaped or elongated. Small branches girdled by cankers can wilt suddenly, fail to leaf out, and die.

Cultural Controls

Prevent stress to trees. Avoid pruning during the summer and fall to prevent infection. Prune off and destroy infected branches during periods of dry weather.

Locations Affected

branches, trunk

Plant Environment

outdoors

Scouting Season:

January - Early , January - Mid , January - Late , February - Early , February - Mid , February - Late , March - Early , March - Mid , March - Late , April - Early , April - Mid , April - Late , May - Early , May - Mid , May - Late , June - Early , June - Mid , June - Late , July - Early , July - Mid , July - Late , August - Early , August - Mid , August - Late , September - Early , September - Mid , September - Late , October - Early , October - Mid , October - Late , November - Early , November - Mid , November - Late , December - Early , December - Mid , December - Late

Plants Affected


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