As we are going through these over 100-degree temperatures causing drought conditions, don’t forget that your trees need water and can show signs of heat stress during this severe heat.

Trees signal drought stress with a number of symptoms, starting with foliage turning from a dark green to light green followed by browning at the leaf margins. You may also notice wilting and, eventually, premature dropping of leaves.

During a drought and high temperatures, in order to conserve moisture your healthy tree can drop a significant portion of its leaves. Usually, this doesn’t kill the tree but can hold them back for a while and they usually recover.

What about my Evergreen?

Evergreen is a bit of a misleading term because even evergreen plants have to shed older leaves and needles, the same way you have hair on your head all the time but you still lose hair every day. Healthy trees can regularly drop up to 10% of their existing leaves during a drought as a way to conserve moisture and maintain health. If they didn’t drop these leaves, they would lose too much moisture through transpiration, effectively a breathing process that takes place in the leaves.

Continue to follow our watering and tree care guidelines for newly planted trees and remember your established trees, as well. They need some extra relief from the heat.

Fanin Recommends

Start spraying the entire tree canopy a few times a week for 30 minutes either in the early morning or the late evening while we are over 100 degrees to help the tree get a break from the heat, knock off any dead leaves or small limbs and reduce the stress. We recommend you get an oscillating sprinkler with an adjustable spray that goes back and forth to cover the entire tree canopy. Remember to keep your fertilizing schedule, as well. For proper tree care during the heat we recommend you up your superthrive treatment to every other week if your tree is showing signs of stress for at a minimum of 2 months.

Signs of Drought Stress in Trees

Signs of drought will be most visible in the foliage of trees. Look for the following symptoms in times of short-term drought.

  • Temporary Wilting. Wilting and drooping leaves will occur during the day. Leaves will recover and appear normal by morning.
  • Permanent Wilting. As droughts progress, leaves will remain wilted even in the early morning.
  • Yellowing Leaves. Prior to dropping foliage, leaves will turn yellow and exhibit fall color. (Figure 1)
  • Leaf Scorch. Leaf margins will have a brown or burned appearance. (Figure 2)
  • Defoliating Trees. Trees will generally begin to lose their leaves from the top and branch ends. (Figure 3)
  • Bark Cracks. During prolonged droughts, trees might develop longitudinal cracks in the bark, especially in thin-barked species like maples. (Figure 4)

Figure 1: Chlorotic or yellowing leaves

Figure 2: Leaf Scorch

Figure 3: Tree defoliating from the top and branch extremities

Figure 4: Bark cracking due to drought stress. Common in maples

Tree Care & Maintenance At Fannin Tree Farm

Need help caring for your trees during the hot months? Fannin Tree Farm offers tips & tricks, as well as tree care service plans to help you maintain your yard or property. Contact us today for your tree care needs.