Answer: Based on your description, I do not think the problem is aphids. (Those would be small soft bodied sucking insects grouped at the tender new growing tips. They can be washed off the plant with a strong stream of water from the garden hose. Usually they do not find their way back.) I suspect your hollies may have some fungal problems, but I can't say for sure long distance. I would suggest you work with your county extension to obtain a specific diagnosis of what is infesting your plants and then based on that, determine how to proceed. If it is something that requires a chemical control, they will have the most up to date information on what to use and the correct instructions for how and when to best apply it. Good luck with your hollies!
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