Holly Disease

Question

I have several young holly plants in a hedge row that are about three years old, grown from whips. Nearly all of them have shown the following symptoms and appear dead:

The leaves have turned yellow/brown, the stem appears grey and mottled. They are grown in a clay soil, in a ridge and furrow field open to the elements.

Could the harsh winter have killed them off? They have survived the previous two winters OK.

Answer 1

It is possible that it is holly tar spot. Let me know if this article describes what you are seeing:
https://www.gardeningknowhow.com/ornamental/shrubs/holly/holly-problems-holly-leaf-spot-or-holly-tar-spot.htm