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Plum Stump Rot and Geranium Black Rot: No Soil Contamination Risk

Old plum cut down; stump used for birdbath. Geraniums nearby got black rot (destroyed). Stump now crumbling. Owner asks if soil is contaminated for replanting.

Answer: Safe to Replant

Wood-decay fungi (on stump) and geranium black rot (likely Pythium/Phytophthora) are different organisms. Decay fungi break down lignin/cellulose in dead wood only—they do not attack living roots or survive as soil pathogens. The rotting stump actually adds organic matter.

Plant freely; no waiting period needed.

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