There a few pests in the caterpillar family that can do similar damage. Nothing life
threatening to your tree, but can make you plant look unsightly. Most times you don’t
actually see the pest but within a few days can see where it has been.
There is one specific little grub that chews through the bark a few centimetres along
young bough tips. The tip becomes ring-barked and the end of the bough dies off.
You usually notice several effected areas on conifers in close proximity. Usually
a quick spray of a systemic insecticide will fix the problem.