This Cedar was planted around 30 years ago. The tree loving person also invested in the installation of a metal guard to protect the young tree from potential harm. They would have watered the tree through its early stages of establishment and watched it grow into a fine young specimen.
What they did not do was remove the guard once the tree was established and free from potential harm. The tree continued to thrive, its lateral meristematic zones enlarged (the tree got bigger) until it touched the sides of the guard. This is when the protector turned grim reaper.
The tree tried to continue its growth, the rails top and bottom started to restrict the cambial layer, this is where the vessels are situated to transport water and nutrients around the tree. On occasions a tree can envelop a small wire or rope and continue to grow – not this time. With nowhere to grow, there was nowhere to go! Death was slow and painful!
If your tree is staked or protected by a guard, keep them on for a minimum amount of time as possible. Stakes – 1-2 years max. Guards – 5 years max.