Ortho malathion 50 plus insect spray this should help. good luck Jim

That happens to my grapefruits, but I don't do anything. I have plenty that mature. I don't know what is causing it, but I don't use any pesticides on my property. The anoles take care of things.

Citrus is the host plant of the Giant Swallowtail. The caterpillars feed on the leaves. If you spray, you could be killing potential butterflies.

How old/large is your tree? Mine is about 12ft high.

My grapefruit tree is about 12 also and very wide. My orange tree is about 15 years old and produces heavily. In the afternoon sunshine in December it looks like a tree with golden fruit; very pretty. I don't mind the damage as much on the grapefruit as I do on the oranges because I like to make Christmas baskets with them.

I use Dr. Bronner's Peppermint Oil Soap about a teaspoon per gallon in a hose end sprayer on my citrus when I see snow scale or any leaf damage. Cleans up the trees nicely and smells great. I do this in the evening so the sun won't burn the leaves.

Treefrog, I have never heard of that product. Where do you get it? Shall have to try it.