Q.Diseased Holly
I have two Holly bushes that have developed what I think is fungus. The underside of the leaves have long white spots. When I shake the branch, small particles fly off. Do you know what it could be and, if so, how do I take care of it? Thank you.
Are the spots powdery in nature. If so, it is is powdery mildew and can be treated with neem oil. Here is more info: https://www.gardeningknowhow.com/problems/get-the-cure-for-powdery-mildew.htm https://www.gardeningknowhow.com/problems/pests/neem-oil-uses.htm
In addition, it could be scale or mealybugs, which can also be treated with neem oil. These articles should help: https://www.gardeningknowhow.com/plant-problems/pests/scale-bug-how-to-control-plant-scale.htm
https://www.gardeningknowhow.com/plant-problems/pests/mealybugs-white-residue-on-plants-leaves.htm