 Well, the thing you add to that problem is you add orange oil in a concentrated form and you paint it on the trunk of the tree where you see the activity of the borers. And if they're still active, the orange oil will soak in. You mix it, the concentrate, like four ounces, four to eight ounces per gallon of water. You do it real heavily and you can spritz it on or paint it on and it'll kill the borers that are active.