Some important tree terms: Learning a little about trees can help prolong their lives in a big way. What is d.b.h.? It is the diameter at breast height. This measurement is taken at approximately four and one-half feet off the ground.

What is the critical root zone? Draw a circle to represent the trunk of a tree. Then draw a larger circle representing the canopy. Be sure to show how far the branches extend. The outer portion of the canopy is called the dripline. The area between the dripline and the trunk is the critical root zone. A good rule of thumb is to allow one foot for every one inch of trunk d.b.h. (“diameter at breast height,” remember?).

Where are the tree roots? Tree roots lie in the top 12 to 18-inches of soil. They are easily damaged by tilling, trenching and digging. A healthy root system will naturally lead to a healthy tree.

What do trees need? Trees need regular pruning. Pruning by trained professionals will keep trees healthy and reduce potential liabilities from falling limbs. The cost of a pruning program is much less than replacing a ruined Lexus. Worse yet, what about a personal injury lawsuit? Can you afford the time and the money?

Trees need soil therapy. Soil amendments must be introduced to help restore the nutrients, micronutrients, mychorrizae and other elements needed for root growth.

Some trees need to be fertilized, some don't. However, when you fertilize a tree, the material should be injected into the soil where tree roots have access. Trees need their space. Remove the turf from under tree canopies and replace it with mulch. Don't replace it with deep rooted plants, as deeper than 6 inch tilling of the bed can destroy essential roots in the tree's critical root zone. Building up the soil around the trunk can suffocate the tree causing poor health and even death.

Trees need protection. Protect the critical root zone. Damage in the critical root zone can kill a tree. Death may not be instantaneous. It can often be a slow three to six year process. Some species can tolerate more damage and loss in the critical root zone than others. Only an arborist can tell you for sure how much damage a tree can tolerate.

Trees need water. Depending on the area, trees may or may not need supplemental watering. Consult a professional arborist for recommendations.

Trees need professional care. Take time to look up as you walk a site. Notice dead or dying limbs. Worry if a tree is prematurely losing its leaves or appears to have an infestation of some kind. Most importantly, call a professional arborist for help when you see any of these signs.

Finding an Arborist: Trees are complex organisms. While shrubs rebound from a bad cut in one season, and grass rebounds in weeks, trees can take years to recover from bad pruning cuts and other damage. Many never recover and the long term effects can cause the tree to fail in high winds or heavy snow,

Protect yourself and your trees by working with a professional arborist with a proven track record. ISA (International Society of Arboriculture) certification is a good starting point, as it attests to an established level of knowledge about trees and their care. Also look for membership in The National Arborist Association. Remember, most states have no state license for arborists. Anyone with a pole saw can say they’re qualified. Be sure to check references, visit properties and trust your instincts when choosing an arborist.