I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
If the tree is gone the bugs are scattering and in fact don't need spraying. They tend to come and go periodically. If you like you can spray them with a product containing neem oil. Make sure and contact the bugs with the spray (spray upward from beneath the leaves).
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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