Sweet Gum Tree Has Caterpillars Eating Leaves And A Dark Damp Stain On Bark

Question From: Irvine, California, United States
Q: i have a Sweet gum tree that a has Dark, Damp Stain on Bark I suspect it is Bleeding Necrosis I would like to know if it sure the tree will die from it and how long does it usually take for the tree to die?. I am in southern California. I see the stain on the bark but other than that the tree still looks healthy. would the leaves still come back in the spring? I also have caterpillars eating the leaves, is that related in any way? i have passion fruit vines right next to this tree, are the caterpillars on the sweet gum the same as the passion fruit ones?
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A: The necrosis and caterpillars are separate issues. I recommend you get an onsite inspection from a certified arborist for your tree. To find one in your area go to www.tcia.org and enter your zip code. Bag up samples of your caterpillars and take them to an independent garden center or nursery for an accurate ID and recommendation for control or let the arborist take care of them. Available products vary from state to state in the U.S. as do pests. Best And Happy Yardening, Nancy