Hello,

Willows have many problems including breakage which opens them to fungi and insects. Seeing ‘sawdust’ indicates insects inside, which may be borers, carpenterworm, or carpenter ants. A professional should go over the tree and give a care plan, including specifically determining what insect is causing the sawdust, whether the insects can be controlled or eliminated, and whether the tree is structurally sound.

Find certified arborists, professionals who have been trained in tree care, pests and diseases, and passed certification tests, by zip code here- www.treesaregood.org 

Use the “Find an Arborist” tab and then search by location or zip code.

I hope this is helpful. Thank you.