I have two holly bushes, both planted this season. The male has a crusty growth at many of the leaf joints, but not all. I can pull them off and they are green underneath - don't appear to be an insect. Is this part of the plant or some fungus?
Possible Pest on Holly Bush
Certified GKH Gardening Expert
It's hard to say but may be a pest, with the crustiness being hardened honeydew. At any rate, neem oil is an effective treatment, be it a pest or fungus. Here is more information: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm