Q.Treatment for worms on mulberry tree?
I just purchased a house in SW Florida and there is a beautiful mulberry tree in the backyard but I noticed the leaves are full of holes. I’d say 30% at least of the leaves are stripped so it seems like a significant problem, but I want to eat the berries so don’t want to cover the tree in chemicals. Does anyone know what these green worms are and the best way to get rid of them so I can still eat the fruit? From what I’ve googled they seem to be silkworms..
Silkworm or fall webworm I'm not sure, but definitely a caterpillar visible in the photo under some webbing. They feed on the foiage and skeletonize the leaves or chew clear through to create holes.
Because its a food plant for you then you are correct to avoid hard chemisty insecticide. But there are botanical insecticides that are non-toxic and biodegrade rapidly and are therefore organic program compatible. Bt (Bacillus thuringiensis) is a biological control, but the caterpillars have to ingest it, so timing is critical for effective control. Pyrethrum is the old standard chrysanthemum extract the is a contact spray and very effective for immediate knock down. Of course the application is dependent how big the tree is and if you have spray equipment to reach the entire foliar canopy. If not you may need to hire a tree service with a plant health care division, or a local pest control company. Screen them on the phone to determine if they will use organic program compatible methods and materials like these:
https://www.domyown.com/evergreen-pyrethrum-concentrate-p-1875.html
