What's causing some of the leaves to not have spikes? Some mutation or is this normal?
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The number of spines varies from tree to tree. I lived in a home that had a very old tree and it only had about 4 or 5 spines on each leaf and was healthy. The trunk was about 10 inches wide.
Sometimes the spikier leaves are concentrated at the bottom to prevent them from being eaten, with the smoother ones at the top of the bush out of the reach of browsing herbivores.
This is what I've heard, and I have seen it on some trees, but definitely not on all...
The tree was surrounded by other trees and there was almost no leaves below 6 feet.
More commonly in that area the holly had 10 or 15 spines per leaf even at 10 feet above the ground. There is little wild holly where i live now but plenty else to see and enjoy.
The comment from Masked Marvel about mostly spiky at the bottom, is what I was always told and my sheep and cattle used to leave these well alone, although attempting to reach the ones without spikes.
Lat/Lng: 51.4526, -2.6071
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