Do no harm: Things NOT to do to trees
One of the most basic principles of tree care is "do no harm."
Vigorous trees appear to be invincible, and individuals are often
negligent without even realizing it. A good example would be the
repeated use of a string line weed-whacker around the base of the
tree to keep the grass trimmed away from the trunk. At first glance,
it would appear that the plastic line couldn't possibly harm a
"tough" tree trunk. But when you consider the velocity of the line,
and the living tissue just below the
tree's outer bark,
you realize that repeated use of a stringline trimmer can open trunk
wounds and subject the tree to destructive, invasive pathogens.
Therefore, be careful using weedeaters around tree trunks, or better
yet, create a protective mulched area around the base of the tree so
weedwhacking next to the trunk isn't necessary.
Don't add soil fill over an existing
root zone unless it is
absolutely necessary. Even though placing a couple inches of soil
over a bumpy root system in the lawn won't usually harm a tree, it's
better yet to create a mulched area or groundcover planting in the
tree's root zone.
Don't leave tree supports and guy
wires wrapped around new trees too long. Check them periodically,
especially during the growing season to ensure they aren't
girdling (choking) the new tree. Tree supports are only left on 1-year
unless there are special circumstances.
Don't leave branch stubs when
trimming off branches. Branch
stubs provide an excellent entry root for destructive insects and
disease pathogens. At the same time, cutting a branch too close to
the tree trunk can remove the "branch collar," which provides a
degree of natural protection to the open wound. Trees actually have
protection ability built right into the branch collar. Therefore,
the second "don't" in this paragraph is: Don't paint branch cuts --
the tree already has natural protection from the branch collar and
painting is unnecessary, even undesirable.
Don't "TOP" trees with "hat rack" style trimming techniques.
If a large tree is planted in the wrong spot and needs this drastic
of trimming, it's better to remove the tree, completely grind out
the stump and plant a tree which
won't grow so large. Topping creates large branch wounds, subsequent weak growth
of fast growing sprouts and basically ruins the natural structure
of the tree FOREVER.
Don't trench close to a tree trunk for utility lines. Since
most tree roots are in the top 24-inches of the soil, digging a
utility line trench between the trunk and the branch tips will effectively remove a
large percentage of the tree's roots, causing problems with water
uptake as well as stability.
Don't plant fast growing trees (Silver Maple, Poplar, Willow,
Bradford Pear, etc) that will rapidly become problems in the future.
herbicides in a tree's rootzone which leach down through the soil
and to be picked up by the tree's roots, causing damage to the tree.
Many dandelion and broadleaf weed killers are known to leach, while
glyphosate is more quickly immobilized in the soil. Don't
spray any kind of weed killer on the trunk, branches or exposed
roots of a tree, while keeping in mind that "thin barked" trees
(like beech) can be especially sensitive to damage from weed