I have had butterfly bushes in northern virginia for over 15 years and then moved to central virginia 5 years ago. This year all 5 of mine are showing the symptoms, some worse than others. They are not all together, but spread around the yard with different light and soil conditions. I thought it was aphids and have been treating with soapy water for over a month. It helps, but seems to just slow the progression. I don't believe it is spider mites because taping the leaves over white paper doesn't cause any dots to appear. And there are no holes in any of the leaves. Any thoughts what it might be? PS, I have other photos if needed

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