Trees, like most other plants, typically go through a growth phase in the spring after being relatively dormant through the winter. The tree puts another ring on its trunk, a sign that it has thrived another year. With the arrival of summer, a tree is ready for its evaluation.
When you need surgery, you don’t ask someone who has taken a few anatomy courses. You rely on a surgeon who has been through medical school and is accredited by a recognized medical association. Similarly, when your trees need attention, you don’t want just anybody with a chainsaw and a ladder, you want an arborist certified by the International Society of Arboriculture. Their website, isa-arbor.com, lists people by city or zip code who have been certified on levels from Arborist through Master Arborist. Using this tool to find a qualified arborist will ensure the best treatment for your trees
Health Signs
An arborist will look for tree defects like dead limbs, trunk cavities, or a thinning crown.
Also, during summer’s heat-induced thunderstorms, trees show their mettle. Weak and diseased trees shed their limbs providing clues as to their health.
Only half the story is above ground
Roots can provide clues to a tree’s health. A good arborist will take a sample of the root and inspect it for weakness and decay. Machines can also graph the drill resistance through a root system to determine the health of the root.
Be careful around your trees
With the prevalence of home additions and renovations, arborists look for the presence of root damage. Roots of nearby trees can be severed when digging a new foundation or soil can be compacted by the use of heavy machinery. Compacted soil deprives roots of oxygen and can lead to a weakened tree in future seasons.
Pests not allowed
Pests include boring insects such as pine beetles, hardwood boring termites, and Asian wooly hackberry aphids (they make the sticky black spots that attack your car paint). An arborist will determine the type of pest you may have and the treatment needed to eradicate them.
Although carpenter ants don’t like live wood, their presence means that there is decayed wood somewhere in the tree.
Summer Maintenance
During the summer, trees typically put all their leaves to work converting sunlight to energy through photosynthesis. It’s usually a good time to prune dead limbs because they’ll be easy to spot: the ones with no leaves. However, arborists caution pruning healthy limbs during the summer because the tree depends on the leaves to make energy and the limbs to channel the nutrient-rich sap to the trunk. Healthy limbs should only be pruned during winter (a tree’s off-season).
Be careful about planting a large tree and then trying to grow grass underneath it. Trees and grass are not necessarily natural allies. They often compete with one another for nutrients in the soil.
Know your trees.
A common mistake is for a homeowner to assume that all trees of a certain type will grow to similar heights and girths. Consider the vast number of species of oaks or crepe myrtles – many grow to varying heights.
Be careful about what you plant.
For instance, the river birch does great on a riverbank, not so great near a patio where it will shed bark which creates a mess and will crack hardscape surfaces with its shallow root system.
Let It Be.
Don’t prune a tree to maintain its size. Monitor it regularly for decay and weakness and let it grow as big as it will.
If a tree must be pruned…
Each removal of a limb with leaves is like taking away a little part of the tree’s food factory. It will spend its energy recovering from the cut rather than growing. Since every pruning cut of a live limb is a wound, only a professional arborist can assess how much a tree can take and still remain healthy.
There are plenty of crepe myrtles in Columbia. Only prune them during the winter, never when leaves are emerging or shedding. Use the summer to enjoy what they have to offer.
A Pruning Felony.
Pruning the top of a crepe myrtle is a crime known as “crepe murder” and should never be done.
Jason Tatem
August 19th, 2010
I was moments from trimming up some low-lying limbs on a tree I have in the front yard that covers both the view of the house, but also makes the tree appear ‘droopy’. After reading this article I’ll just wait until winter, that makes absolute sense not to kill off the food-supply mid-dinner.
Thanks for that tip, and thank you for your magazine and all the writers!