Oak Tree White Suds After Rain: Harmless Residue

30-year-old oak: heavy rain caused white soap-suds-like foam at trunk base, running down bark. Never seen in 30 years. Owner asks if disease.

Likely Explanation

Rain washing accumulated dust, pollen, chemicals off bark—creates foamy appearance. No known disease matches.

Bacterial wetwood (slime flux) causes frothy discharge but from dark-stained trunk area—not described here.

If tree leafs out fully, it's harmless. Monitor for other symptoms.

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