Live oak. iStock photo by Leslie Quiroz
This time of year, we are generally advised to trim oaks for the diminished risk of oak wilt. Yet our trees have only received 9-10 inches of rain this whole year. The optimal amount for oaks is 3-4 inches a month.
So, what do we do about our drought-stressed trees? Have you been able to water your trees? Can you look at your yard and tell which trees are farther than your hose reaches?
“Most trees usually die from a combination of different stresses,” said Courtney Blevins, Texas A&M Forest Service urban forester. “One of the biggest stresses we see in Texas is drought. When that happens, stresses build up and secondary pests or diseases can establish in trees.” (AgriLife Today)
Secondary pests are insects that take advantage of the declined health of a tree such as termites, carpenter bees, and carpenter ants.
As with most living things, water is important to the survival of the species. This also holds true of trees. Water is necessary not only for trees to photosynthesize — creating their sugars, food, and nutrients — but also to move the nutrients through the trees. A lack of water will result in physical malformation of the tree, such as wilted leaves, loss of turgor pressure within the limbs, or a complete brownout where all of the leaves drop.
If your trees are showing signs of stress don’t prune.
“What you’re trying to do is reduce stress to the tree, so pruning, even when you have to, is adding stress because you are wounding the tree,” Blevins said. “If you’re pruning out, live branches or live leaf areas of the tree, you’re removing food and the site where the tree’s root growth hormone is developed, affecting root growth and further stressing the tree at a time when it’s already too stressed.” (AgriLife Today)
A few more tips:
- If the branch is completely dead, it is OK to remove it from the tree. Be wary of where you place the dead limb; it’s brushfire fuel.
- If you’re unsure if a small tree is dead, use the thumbnail test. Make a scrape with your thumbnail on a limb or trunk. If there is green underneath, your tree is alive.
- Do NOT blindly apply fertilizer to a stressed tree without checking the soil. Adding fertilizer when it’s not needed could harm your tree, even by burning the ends of the roots.
- Supplemental water is dependent on your tree and area.
You can find a certified arborist online.
Remember the True Master Gardener: Jesus said, “I am the vine; my Father is the Gardener.” John 15:1
"In the Garden" is written by father-daughter duo Bill and Martelle Luedecke and Bill Luedecke. Contact Martelle at 512-769-3179 or luedeckephotography@gmail.com. Contact Bill at 512-577-1463 or bill@texasland.net.
Find more "In the Garden" columns in the Lawn & Garden Guide.
