You may have woken up to some leaves on your front lawn recently, and while it may look like fall has arrived, that isn’t the case just yet. 

Like all plants, trees need a regular drink of water to stay healthy, but rainfall can sometimes be hard to find during the summer months. A stretch of hot and dry weather (like we saw during the first half of August) can force trees into experiencing heat stress, where they will be losing water more quickly than it can be replenished. 

 

Trees lose water through a process called transpiration, where water vapor is released through the leaves of the tree. The high heat and dry conditions increase the rate of transpiration, forcing the tree to conserve water wherever it can. 

One way trees can conserve water during these hot stretches is by dropping leaves. By losing leaves, a tree can reduce its surface area exposed to the heat and can redistribute water that it would be sending to the leaves to other locations. 

 

Certain types of trees are more vulnerable to heat stress than others. Beech trees, sugar maples, and gray birch trees are just a couple of heat-vulnerable species that you can find in Northeast Ohio. 

If you notice your trees dropping leaves during these hot summer days, there are steps you can take to make sure they are getting the water they need. Placing a layer of mulch around the base of the tree can help it retain moisture better, and making sure to water the trees on your lawn during the summer can help them stay healthy.