While it's wonderful to have a professional lawn maintenance crew to keep you from braving the sweltering summer heat to cut your lawn, their heavy-duty machinery can sometimes unintentionally damage your trees. Young trees are especially susceptible. Taking extra steps to protect the tree's tender bark and roots can save you future heartbreak.
Barriers to Protect Tree Trunks
When trees are small, they often come with black plastic protective tubing around the bottom of the trunk, but many times, that is not sufficient to guard against damage. These guards can slip up and down and can damage the trunk if they are not removed before the trunk outgrows them. You should actually have two layers of protection around tree trunks to guarantee their tender bark is not sliced into by mower decks and string trimmers.
Sturdy Barriers Are Best
While those inexpensive plastic borders are cute, they aren't sturdy enough to protect your trees. To really guard against machine damage, you should use landscape timbers, concrete rings, bricks or border blocks. These stand up to being bumped by mower decks and industrial strength trimmers for sturdy, long-lasting protection.
Why You Need a Two-Step Barrier
The bark of your tree should never touch the mulch around it. Mulch against the trunks can breed disease and insects that can cause irreparable damage to your tree, even resulting in its death. Therefore, you need an inner barrier about six inches out from the trunk and an outer barrier further out to hold the mulch and create the machine exclusion zone.
The inner barrier doesn't necessarily need to be as sturdy as the outer barrier, since it won't be in contact with machinery, but it needs to be sufficient to hold the mulch away from the trunk. Black landscape edging is often sufficient for this purpose.
About the Mulch Ring and Outer Barrier
For some trees, such as fruit trees, you need to mulch all the way out to the dripline. This is where your sturdier outside barrier should be placed. It should be tall enough to hold a 3-inch thick layer of mulch, which not only holds water and fights weeds, but protects any surface roots from mechanical damage. Larger trees don't need such a huge mulch bed, so their barrier is mostly protective, and can be placed about 12 inches out from the inner barrier.
Black PVC landscape edging material is not suitable for a permanent outer barrier, because it deteriorates quickly and often sinks down into the ground. It is sufficient as a temporary solution for budget purposes, though, because some kind of protection is better than none.
Remember that it is your responsibility to protect your trees from mechanical damage from lawn maintenance machinery. If you want more information about how best to keep your trees safe, ask your lawn maintenance team like The Cutting Edge Lawn and Landscaping LLC.