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Curly Willow Trunk Burls and Cicada Holes: Benign and Seasonal

Trunk Growths = Burls

Oblong, tube-like bark structures that dry and fall off are burls—bacterial-induced benign tumors (Agrobacterium tumefaciens). They don't harm the tree and are prized by woodworkers.

Ground Holes = Cicada Emergence

½-inch holes with brown shells are periodical cicada exit holes. Nymphs emerge after 13/17 years, molt, and adults sing at dusk. Egg-laying in twigs causes minor flagging, no lasting damage.

No Action Needed

Both phenomena are natural, cosmetic, and self-limiting. Enjoy the cicada chorus; admire the burl's future wood figure.

Trees: Curly Willow Sucker Management: Why Wrapping Fails and Pruning Works; Planting Curly Willow: Fall Planting, No Fertilizer First Year; Growing a Curly Willow in a Container; Maple Basal Sprouts: Mechanical Removal Best, Avoid Herbicides; Globe Willow Bark Peeling and Borers: Water Stress Is Root Cause; Curly Willow Planting in Zone 8: Site Selection and Care; Curly Willow Summer Leaf Drop: Water, Borers, or Shade Competition?; Willow Pruning Bleeding: Normal, No Seal Needed; Mushrooms on Birch Trunk: Sign of Decay, Not Immediate Death; Old Willow Borers: Insecticide + Fertilizer for Recovery

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