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Pear Tree Orange Leaf Spots: Pear Rust

Wall-trained pears have bright orange circular spots on leaves with raised pointed clusters on undersides—pear rust (Gymnosporangium sabinae), a fungal disease alternating between pear and juniper/cedar.

Management

Remove nearby alternate hosts (junipers) if feasible.
Rake/destroy fallen leaves.
Fungicide sprays at bud break, repeat per label (mancozeb, myclobutanil).
See UAEX Fact Sheet FSA-7538: Cedar-Apple Rust (similar cycle)

Note

Rust rarely kills but defoliates and weakens. Adobereader needed for PDF.

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