Something is crawling on my key lime leaves, leaving tracks. It is apparently causing the leaves to cup & curl -- each has a "track" mark. I've picked off a few strange looking caterpillars, both large & small, but can't always find them. Also, a huge grasshopper looking insect is eating the leaves -- have pulled him off also when found, but he returns. This large critter also flies. How can I rid the tree of these pests? Thank you.