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Elm Trees with Holes in Leaves: Elm Leaf Beetle Damage

Multiple elms in Colorado show shot-hole leaf damage. One removed due to weakness/branch breakage (arborist blamed squirrels). Two transplanted saplings from same soil now show same damage. No visible insects.

Diagnosis: Elm Leaf Beetle

Classic shot-hole feeding; adults and larvae often unseen. Colorado State University fact sheet (05521) provides identification and control options.

Management

Monitor for larvae on leaf undersides in spring. Systemic insecticides (e.g., imidacloprid) applied early can protect canopy. Maintain tree vigor—stressed elms attract more beetles.

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