Frothy Flux on Weeping Willow: Manage, Don't Panic

A weeping willow in Alameda, CA exudes clear, gelatinous froth—likely frothy flux (also called frothy canker). It's a yeast-driven fermentation in the cambium, often entering through wounds. Not a true pathogen, but a secondary invader.

Management Strategy

Large, healthy trees often outgrow it. For stressed trees:

1. Boost vigor: Fertilize with 10-10-10 at 1 lb per inch of trunk diameter, scattered at drip line and watered in. Apply before rain or irrigate well. Repeat in spring.
2. Water deeply but infrequently: Allow soil to dry several inches down between soakings.
3. Excision (if localized): Cut out infected bark to hard wood, disinfect knife in 10% bleach between cuts, soak wound with bleach solution, leave open to air. Do not remove >50% of trunk circumference.

What to Avoid

Don't paint or wrap wounds. Don't over-fertilize (causes weak growth). Monitor annually—flux may fade and return.