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Iris Borer Control: Sanitation, Scouting, and Physical Removal

Mushy rhizomes and collapsing fans indicate iris borers. Moths laid eggs on dead foliage last fall; larvae bored down leaves to rhizomes by July, introducing rot.

Immediate Action

Dig and discard severely infested rhizomes
Lightly damaged: scrape rot, dust with Captan, replant

Prevention Calendar

March: Remove ALL iris foliage from property
May-June: Scout leaves for notches; squeeze below notch to kill larvae inside

Diligence avoids insecticides. Physical control works if consistent.

About Gardening: Sap Leaking at Cottonwood Base: Likely Borer Damage; Natural Garden Pest Control: Encouraging Beneficial Allies and Managing Common Pests; Organic Garden Pest Management: Ecological Strategies for Healthy Crops; Effective Pest Control: Prevention, Detection, and Action; Dealing with Lawn Pests: Identification, Treatment & Prevention; Stopping Birds from Attacking Windows; Homeowner Pine Beetle Response: Removal Timing, Chipping, and Protecting Neighbors; Safe Slug Control with Iron Phosphate; Growing Iris from Seed: A Step-by-Step Guide; Storm-Damaged Trees: Assessment, Recovery, and When to Call an Arborist

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