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Indian Bean Tree (Catalpa) Wilting with Rotten Core: Verticillium Wilt Confirmed

A 5-year-old catalpa showed sudden wilting on half its branches. Pruning revealed black, soft, 3–4 mm diameter rotten cores. The owner feared spread to a nearby valuable maple (Acer).

Diagnosis: Verticillium Wilt

Jen identifies the classic symptoms: branch wilt, internal discoloration (streaking under bark), and blackened centers from secondary decay fungi. Verticillium is soil-borne and persists for years.

Immediate Actions

Remove all wilting branches promptly, cutting into healthy wood.
Sanitize tools between cuts.
Do not disturb soil around the tree; pathogen spreads via root contact and soil movement.
Avoid planting susceptible species (especially maples) in the same spot.

Resources: UNL Verticillium Wilt | PNW Handbook | NMSU Circular

Plant Diseases: Ash/Hickory Leaf Spot: Fungal Disease Management and Tree Identification; Indian Bean Tree (Catalpa) Black Fall Leaves: Sooty Mold from Insects; Hypoxylon Canker on Holly Tree: Gas Leak Connection?; Catalpa Worms on Indian Bean Tree: Identification and Organic Control; Mature Ligustrum Splitting and Declining: Age, Weather, and Rot; Indian Bean Tree (Catalpa) One-Sided Dieback: Borers or Branch Damage?; Plum Tree Sap Flow and Dieback: Signs of Borers; Sawdust Threads on Oak Tree: Wood Borers or Caterpillar Frass—Diagnosis Steps; Natural Lower Branch Loss in Mature Pines; Pine Branch Droop and Bark Stain: Normal Aging, Not Disease

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