Assess the Damage

The freeze caused some degree of branch dieback in many of our local trees, primarily in species that are at the north end of their cold hardiness range. For some species such as crape myrtle and vitex, the tree may have died all the way to the ground. Fortunately with many of these trees, we have seen a lot of sucker growth forming at the base. These sprouts can be retained to gradually rehabilitate the tree.

Other trees may have some live foliage, with varying amounts of branch dieback. When determining next steps in tree recovery, consider how much of your tree has died back from winter injury, and furthermore, how much has been lost due to ice damage this year. If more than 50 percent of the canopy has been affected, Urban Forestry recommends considering tree removal, as the tree is unlikely to recover.

If the tree still has more than 50 percent of its canopy, there is hope for rehabilitation. In these instances, it is important to prevent further tree stress. Urban Forestry has a couple of resources that may be helpful: Tips for Tree Recovery and Tips for Growing Healthy Trees. Texas A&M Forest Service also recently posted this helpful article with information about the impacts of the February storm on trees and additional recommendations for tree owners: What to Do With Trees Recovering From Winter Storm URI.

Urban Forestry recommends hiring an International Society of Arboriculture (ISA) Certified Arborist to perform a Tree Risk Assessment and pruning/removal, especially when dealing with larger trees. A Certified Arborist has demonstrated knowledge and experience with proper and safe tree care practices. You can find a local arborist by searching with your zip code at this link: Find an Arborist.

Water Your Stressed Trees, and Apply Mulch

The summer heat has arrived, and rains are less frequent. Under these conditions, a little supplemental water can go a long way in helping to prevent an already stressed tree from declining into even worse condition. This is certainly true of recently planted trees, but established and mature trees can benefit from watering during these times as well. Check out Urban Forestry’s Guide to Tree Watering for tips on watering methods.

Mulch is also a very beneficial tool that not only helps to retain soil moisture, but also adds minerals into the soil, encourages fine root growth and regulates soil temperature. Trees can benefit from a 3-4” thick layer of mulch spread as far from the trunk as the drip line, or the edge of the canopy. That can be a significant area for large trees, but as much as you’re comfortable with providing can be helpful for the tree. When applying mulch, always make sure that it is not piled against the trunk – rather, pull it away from the trunk by a few inches to avoid potential for trunk decay. View this Proper Mulching Techniques fact sheet for tips on how to help your tree benefit the most from mulch.

Use Proper Pruning Techniques

After a storm event, the discouraged practice of topping inevitably starts to appear all over town. Topping is the indiscriminate cutting of branches that can cause significant stress for trees and create a bigger maintenance problem for tree owners in the future. Learn more about topping at Why Topping Hurts Trees. It can be overwhelming to visualize how to restore a tree’s structure after it has experienced a lot of damage or dieback from a storm event. This is one reason why it is so important to work with a qualified professional, such as an ISA Certified Arborist, who will be best equipped to perform restoration pruning utilizing proper techniques… or know when to make a recommendation for removal.

When making pruning cuts, always prune back to a branch union, just outside of the branch collar (swollen area at the base of the branch). Pruning at this location will help the tree to produce growth that will gradually close around the wound to seal it off, while stub cuts leave opportunity for decay to enter the tree. View more information about pruning at Pruning Young Trees and Pruning Mature Trees.

When dealing with trees such as crape myrtle that have died back to the ground, cut the dead stems as low as possible, trying to avoid damaging the new sprouts. Over the next few years, these sprouts can be thinned and trained to create good structure for the regeneration of the tree.

Tree recovery can take time, but through incremental care using recommended practices, tree owners can begin to restore their trees to provide benefits for many years to come.

View more topics from the Summer 2021 issue of Edmond Tree Mail