Trees can be the most important items in a landscape for many people. For many, a tree may hold a special value because some were planted by a relative or planted to celebrate the birth of a child while some trees are where the family cookout has always taken place.
We need to keep in mind with trees that all trees will eventually die. A tree is a living organism, so trees can have issues due to injury, disease or environmental conditions at the time. Keep in mind that different tree species have different life spans. A white oak in normal forest conditions can average 300 years while a red maple can live 100 years. It is amazing to think that some trees that are very old could now be the shade giver for a family having a picnic, but at some point gave shelter to a traveler that had been riding a horse and wagon.
I will be sharing information form a UGA circular by UGA staff Mary Carol Sheffield, Ellen Bauske, Wade Hutcheson and Bodie Pennisi.
One point to keep in mind is that trees normally do not die overnight. Trees will normally decline over several years before going into a death spiral. Once a tree hits this spiral, there is not much you can do to fix the situation. Remember in the opening paragraph, I gave the average life spans for a white oak and red maple. These life spans can be reduced by external pressures which can be seen in signs of stress or decline. It is suggested to look for signs such as tip dieback, leaf or needle yellowing or browning, leaf or needle defoliation, leaf shedding, undersized leaves and thin tree crowns or canopies. When you do a visual appraisal of a tree, try to evaluate all parts of the tree. You need to look at roots that are visible, trunk, tree limbs and leaves. I will add that it will be easier to evaluate a tree when they should be in full foliage, such as a deciduous tree in summer.
Before we go through tree evaluation tips, here is one important point to keep in mind. If you are unsure of the health of a tree, particularly if the tree is near a home or business that could make the tree a potential hazard for people or property, you need to seek the advice of a certified arborist professional. A certified arborist is trained and has earned credentials normally with the International Society of Arboriculture through testing and years of experience with other professionals. A certified arborist can determine the overall health of a tree and make expert recommendations on care. An arborist can also determine if the tree is a risk to people or property and may suggest removal. On the other hand, arborist consulting may help preserve tree health and safety, and may help a tree live longer.
I will add that county agents do look at trees and I do often, but agents are not certified to do hazard assessments of trees like an arborist would do if hired.
When evaluating a tree, start at the base of the tree and look at the root system and the root flare of the trunk. Do you see fungal bodies such as mushrooms or conks growing on the ground around the root system? If you seed these fungal bodies, this is a sign of severe or advanced rot in the trunk or root system of the tree. Root decay issues cannot be reversed or fixed so this will cause the tree to be less stable. Root decay is a sign that the tree is in a death spiral. If the root system is failing, the tree will decline and the tree can fall. You also need to look at the trunk flare at the tree base. A healthy tree will be wider at the base where the tree meets the ground. Inspect the flare areas for signs of injury. This is where you can see weed eater or lawnmower damage or damage where a person backed a car into the tree. Injury can reduce the flow of water and nutrients, less vigor and can lead to structure issues.
Construction damage can also be a problem with trunk flare areas and also issue when roots are covered with soil. Most roots are in the top 12-18 inches of soil so they can be damaged by all kinds of construction from septic lines, sidewalk work or soil grading in the root zone. Remember to also look at the actual trunk of the tree. Look again for fungi growth which is a sign of internal rot. Look for areas of bark damage or signs of disease. Look for cankers on the stem or branches or even physical damage in the bark. Bark damage can slow nutrient transportation and can result in dieback of branches and limbs.
Finally, look at the branches and leaves. Do the leaves look healthy? Do you see leaf spotting? Do you see insect or disease damage? Do the leaves look of normal size and color? Leaf injury can be the result of many things such as drought or insect damage for example. Leaf issues could be temporary. Early leaf loss may be a sign of branch dieback and a more serious issue at the same time early leaf loss could be a temporary stress caused by drought or disease that does not cause long term issues. You can look for dieback which are defoliated limbs or twigs seen out of the tree canopy. Dieback can be a sign of other issues such as internal decay.
For more information, contact UGA Extension- Gordon County at 706-629-8685 or email firstname.lastname@example.org.