Disease on holly shrub

Question

Why did the trunk of my holly bush turn black?

Answer 1

This could be caused by Scale, which it them will result in sooty mold--the black on the stems.
I would treat the plant with Neem OIl.

https://www.gardeningknowhow.com/ornamental/shrubs/holly/diseases-of-holly-bushes-pests-and-diseases-damaging-holly-bushes.htm
https://www.gardeningknowhow.com/plant-problems/disease/how-to-get-rid-of-sooty-mold.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm