As the summer heat really comes to a head, you may have noticed that your trees aren’t taking it so well. As of late June, many areas in the South, Southwest and Midwest are already at abnormally dry conditions, with most of the High Plains experiencing extreme drought. A drier than usual Spring does not bode well for urban trees that must cope with the added stress of drought on top of the usual heat.
How Can I Tell if my Trees Are Stressed?
There are a few symptoms to look for that will tell you if your tree is stressed from drought. Wilted and yellowing foliage is easy to spot. Undersized leaves, leaf scorch and premature fall colors are also signs your tree is suffering. You may even notice stunted twigs and deformed buds.
One of the biggest indicators, however, is insect infestation. Trees that are stressed are much more susceptible to life-threatening invasion by beetles, borers and disease.
How Can I Protect My Trees This Summer?
Apply mulch (but do it correctly).
Mulch does wonders for keeping the soil cool and moist, even on the hottest of days. Spread 2-3 inches of organic mulch past the tree’s drip line to reach its feeder roots, which are responsible for most of the water intake.
Note: Don’t pile mulch up against the tree’s trunk – this is called “volcano mulching” and it can kill your tree!
Turf grass competes with trees for water and nutrients, which is why it’s best to replace it with a layer of mulch. Grass under a tree’s canopy will absorb water at the surface before it can reach down to the tree’s roots. This means more water is required, but your tree is getting less – a bad combination during drought.
Trees like to be watered deep and slow. The rule of thumb is to water to a depth of one foot, since most of a tree’s active roots are less than a foot below the soil. Drip irrigation is your best bet at effective watering with minimal runoff. If this isn’t possible, a sprinkler directly beneath the tree’s canopy will work fine.
It’s also important to understand what type of soil you have. Clay soils have poor absorption and need longer watering intervals, while sandy soils require shorter intervals more often.
During drought conditions, mature trees need deep watering every 5-7 days. Young or transplanted trees need more attention; every 2-3 days is best. Try to avoid watering in the afternoon, when evaporation is high. Morning is the ideal time to water. (Be sure to check with your city for water restrictions.)
Light thinning of diseased or dead limbs will reduce the demands for water and allow the tree to focus on its healthy branches. Ideally, this should happen before the summer heat sets in. Trees should not be heavily pruned during a drought, as this will further stress the tree. You can hire the Fort Worth certified arborist service for pruning the hard-to-reach trees.
Fast-release fertilizers impede a tree’s water utilization, making drought conditions even more dangerous for the health of the tree. Slow-release fertilizer can be used, but it won’t help your tree much during hot, dry conditions.
Avoid planting and transplanting.
Planting and transplanting is very stressful for trees, which is why it’s never recommended during a drought. Spring or fall is the best time to transplant.
The best offense is a good defense – a healthy tree will always be better equipped to handle drought stress. If you notice any symptoms of stress (most often from diseases and insects), schedule a consultation with your local tree care service.
Removing dead trees is an expensive process, and it can take decades for new shade trees to grow to size. Taking action now, before trees become stressed, can make a huge difference in the life and health of your trees.