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Lilac with White Spots and Curled Leaves: Herbicide Injury Suspected

Two Separate Problems on Lilacs

White spots on bark and curled, twisted leaves/blooms appear on multiple lilacs after weed killer use nearby. The plant hadn't leafed out yet when sprayed.

Expert Analysis

White spots: Likely lichens (superficial fungus/algae), not disease.
Twisted growth: Classic symptom of growth-regulator herbicides (e.g., 2,4-D). Even if buds were dormant, injury can occur. Roundup (glyphosate) does not cause this.

Outlook

If the herbicide dose was low, the lilac may grow out of it over time. Avoid future drift; apply herbicides on calm days.

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