Answer: The leaves will fall from your pussy willow tree soon so you don't need to do any spraying. Just rake the fallen leaves and remove them from your garden. Without seeing the pest, it's difficult to make a control recommendation. I think the best approach is to watch the plant closely next summer to see if the leaves are damaged again. If so, carefully inspect the plant for the critter responsible. If you can't identify it, capture a few in a plastic baggie and take them to your local garden center for help in identification. Once you know the enemy you can choose the appropriate control.
Best wishes with your landscape!
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