1. Trunk Damage

Vertical cracks, hollowing trunks, dead branch stubs, and unhealed wounds are often indications of potentially serious internal decay. While many tree species can survive for quite some time with a partially hollowed trunk, their lack of structural integrity makes them especially dangerous.

When a tree's canopy consists of 25 percent or more dead or dying branches, it is a good sign that something is wrong. Make sure to have the tree examined by a professional to determine whether it needs to be removed.

Dead branches that are noticeably clustered on one side of a tree could be evidence of serious root or trunk damage on that side. Such trees pose the danger of falling limbs as well as compromised stability.

Shoots and sprouts that originate from either the base of the tree or higher up on the trunk itself are usually a response to major environmental stress, such as adjacent construction or sudden over-exposure to sunlight after forest thinning.

While mushrooms often grow harmlessly at the base of certain species of tree, fungi growing on the roots, trunk, or branches of the tree itself may indicate internal rot or root disease.

Nearby excavations, construction, root disease, and insect predation can all cause serious root damage, leading to leaning and lopsided trees. In general, a tree that is angled more than 15 percent from the vertical should probably be removed.

Trees planted beneath power lines can pose a major fire hazard. During wet conditions, electricity can arc up to ten feet to nearby foliage, potentially causing power failure and catastrophic property damage. Due to serious electrocution risks, a professional arborist should always handle pruning, trimming, or removal of trees beneath power lines.

Even if your backyard tree has just begun to show signs of decay or deterioration, it is always a good idea to get a professional assessment as soon as possible. In addition to forestalling costly property damage and unexpected hassle, responsible tree management can prevent potentially fatal accidents.

Excepting emergency branch removal, pruning (and particularly extensive pruning) should always take place during late autumn or winter. Like all living things, trees are susceptible to stresses caused by physical damage. During the colder months, however, trees are mostly dormant, making them less vulnerable to sap loss and growth stress. Additionally, since insects are also mostly dormant during the winter, they will be less likely to cause further damage to newly pruned areas. You should keep in mind that the best time and method of pruning can differ from species to species. When in doubt, feel free to contact a certified arborist to get an expert opinion on timing, approach, and any safety concerns.

Since trees are susceptible to stress from pruning, it is also important that you make sure not to cut back too much at one time. In general, you should try to prune as minimally as possible, and never take more than about a quarter off the crown of the tree. As well as being a locus of new growth, the crown is the primary energy source for most types of tree, making it risky to prune too much too quickly.

Responsible pruning can also be a good way to manage the growth and ultimate configuration of your trees. In addition to avoiding conflict with power lines, buildings, walkways, and drives, careful trimming can actually improve the tree's overall structural integrity. By removing extraneous, awkward, or damaged limbs, you can also prevent future issues with falling branches and poor weight distribution. Proper pruning can also keep backyard trees looking their best, promoting even growth and improved aesthetics.

While smaller trees may not pose much of a problem, you should always keep in mind that large trees are best left to the pruning professionals. In addition to having the right tools for the job, these trained technicians will be able to get the work done quickly, safely, and without undue damage to the tree itself.