Q.Why Would A Yucca Plant Bug Be On My Azellas?
There are tiny red headed and black body insects on my azellas. The best picture identification of this is the yucca plant bug. This same bug was here last year. one lit on me and bite me leaving a 20mm red circle. The bug itself is only about 1-2mm. I live in East TN and we have had excessive amount of rainfall. Same apply for last year.
Certified GKH Gardening Expert
It doesn't sound like a lace bug, which is problematic for azaleas. Here are common pests of yucca plants, as well.
https://www.gardeningknowhow.com/ornamental/shrubs/azalea/common-azalea-problems.htm
https://www.gardeningknowhow.com/ornamental/foliage/yucca/yucca-plant-bugs.htm