By David Wall
Our spring/summers for several years have given us heavy spring rains followed by flash droughts starting in June or July, and many yards are now in drought stratus even though it’s winter. Current patterns indicate a similar drought can be expected in this summer. While we try to ensure our lawns and gardens get plenty of water, we often neglect or just ignore our yard trees.
The first casualties in a drought are the tiny feeder roots. They may die off over a 2-4 month drought, but it can take as long as 2-4 years or longer to get all of them back. In the mean time, the tree continues to suffer, and growth slows or stops. Not only that, tree girth may actually shrink.
Water with nutrients has to move upward, and liquids packed with sugars have to move downward for to the root system for storage and feeding the microbes in exchange for nutrients. A drought interrupts this continuing cycle and puts the tree in stress. Without enough water to continue, photosynthesis stops, and leaves curl and die. Now, the tree is in deep stress, but tries to continue the sugar/nutrient exchange with microbes.
If the drought is sudden, a tree can look fine, but one day in a puff of wind, a good sized limb suddenly snaps off and falls to the ground. Bigger trees are impacted more due to the extended length water has to travel, and the amount of water needed. Additionally, in a weakened state the tree is more vulnerable to disease and freeze damage.
During drought, provide at least 1” of water from 10’ out (closer for young trees) to past the drip line. Root systems will go at least that far and probably much farther. Do this at least once a week.