Simply cut off the loose bark and give the tree a chance to heal on its own. You may notice cavities in the wound, but don't remove it. Some sources recommend reattaching the crust with adhesive tape or using a wound dressing, but this can worsen the problem. A damaged tree produces compounds in the wood cells that form a barrier to partition the decaying area.
Digging into the wound can damage this barrier. One of the most dangerous pests for trees is humans, especially with equipment. Tree injuries caused by a lawnmower or brushcutter can seriously threaten a tree's health. Damage caused by a lawnmower and a wire trimmer usually takes years to kill a tree.
Wounds close to ground level tend to go unnoticed with normal tree growth for a few years. Wounds of this type are a perfect source of fungi and bacteria that silently invade the tree's vascular system, starting its decline. Grass or mulch near the base of the tree often camouflages the wound for years. After a few years, the tree's growth slows and the tree appears anemic and weak.
Weak, declining trees are easy prey to secondary insects and other plant diseases, causing the tree to eventually die. By reapplying this piece of bark, as a missing piece of the puzzle, and taping the damaged area to prevent insects and other diseases from damaging the tree during its recovery, the tree should heal for a period of 3 to 6 months after being wrapped and cared for. Exposed roots are endangered because lawnmowers run over them and cut off their bark (see photo above). The tree was not hit by a car, surrounded by rabbits, bitten by a beaver or chewed by field mice, but was injured by a human with a lawnmower and a thread trimmer, in repetitive abuse under the pretext of trimming the grass.
The stems of the branches are the only thing left in much of the tree where death was pruned, leaving a scarecrow crooked from a tree with a small handful of weak leaves that do their best to hold on. If you work in a yard where trees grow, it's important to avoid running into them with your garden equipment. But accidents do happen and sometimes you're faced with a situation where you have a wire trimmer too close to the tree or you hit a tree with the lawnmower. Wounds, large and small, make the tree susceptible to diseases, fungi and tooth decay, not to mention that they can cause structural problems in the tree.
Sometimes, weedy seedlings are too well rooted to simply pull them out, and just cutting them causes them to sprout vigorously. The key is not to leave the damaged tree unattended, and there is a very simple way to help a damaged tree after a lawnmower has removed a piece. Wounds that cross the tree's bark damage the ambium layer, which is the vascular tissue that moves water and nutrients from the roots. If the outer protective bark is damaged and the ambium layer is injured, figuratively the tree is left to bleed to death.
The site of injury is usually the root area, where the tree meets the grass and gets in the way of the mower or trimmer. The most serious injury now occurs when the tree's bark slips in early spring, during leaf emergence, and early fall, during leaf fall.