High temperatures and long-term drought can have a profound effect on tree roots. Unfortunately, many times we do not learn this until we see the telltale signs of stress. Once stressed, trees are more susceptible to insects and diseases. Depending on how much root loss has occurred, a stressed tree may or may not survive.

This tree is showing signs of Flux, which is an indication of stress. Click HERE for more info.

It is important to be PROACTIVE to prevent stress in our trees. With a little bit of knowledge, many tree issues may be avoided and our trees will thrive.



*Pay attention to weather forecasts that predict higher than normal temperatures or windy conditions that will cause the tree to require increased watering frequency due to increased transpiration.

*Send the tree into the day hydrated. If you wait until late in the day to water, the tree will be experiencing the lowest moisture content in the soil at the hottest part of the day. The early morning hours are best, as winds are generally calm and evaporation will be less.

*Application of 2″ of mulch under the tree canopy, when possible, will help hold moisture in the soil. Do not allow the mulch to touch the trunk of the tree. 

*It generally takes about 2” of rain or irrigation water to adequately water an established tree. This will vary with different soil types, but the water should penetrate the soil at least 10” deep. Use a sprinkler with large water droplets so that the water can penetrate the soil. Drip irrigation that covers the entire area under the canopy is also advised.

*During extreme heat or drought conditions, established trees should be watered weekly under the entire canopy, NOT just at the base of the tree. If water is in short supply, focus the watering from about halfway between the trunk and the edge of the canopy all the way to the edge of the canopy.

*Fact: Tree roots can grow 2-3 times the height of the tree OUT from the tree. This is where established trees should be watered, NOT just at the trunk!

*Fact: The majority of tree roots involved in the absorption of water and nutrients are in the top 1’-2’ of the soil. Roots require oxygen, and that is where they will find it. Infrequent, deep watering will encourage root production in this zone.