Through the years during times of high temperatures and low moisture content in the turf areas, we can start to see signs of stress in our lawn. During these times, following a lawn mowing, you may notice “tracks” in the turf that appear to be dead and may wonder if the damage was caused by mowing or a fertilizer application. Typically, fertilizer does not cause the issue. It’s the direct contact of the fertilizer or mower wheels (or even footsteps) causing the problem. The damage occurs when the turf is starting to wilt, and traffic is put on it. Anything driven over the turf when it is wilting will cause heat track damage.
The condition of the turf is the primary key to the cause of the tracks forming. When a lawn is entering drought stress, even though it may still be green, it can be susceptible to this form of damage. Wilting happens when the root zone doesn’t have access to water in the soil.
During the blistering heat of summer, the top few inches of soil can dry out quickly (usually mid-morning). If the roots of the lawn are no deeper than the dried-out soil then the lawn will begin to wilt. This process continues to repeat itself with the poor practice of daily short watering. The wheels of a mower, or even the imprint of a shoe from walking on the turf bends and breaks the stressed (wilting) leaf blade. The leaf blade is no longer able to stay green and turns brown as it dies off. The good news is the roots and the crowns of the turf-grass are not affected, just the grass blades are damaged, and the turf is not dead. The lawn should recover in 2 to 3 weeks. We encourage you to follow these few steps to avoid heat tracking in your lawn.
Help manage heat track damage by increasing your watering. Rule of thumb is to water turf areas infrequently but DEEPLY. If you water a little bit every day, it encourages the roots to stay “shallow” and increase the chance of heat/drought stress. For a useful guide, we recommend reading Proper Watering Techniques to Obtain a Healthy & Beautiful Lawn on our website.
Mowing the turf area at a height of 3 inches or above and altering mowing patterns as to not follow the same wheel track week in and week out. When the lawn is taller it helps prevent heat stress, we recommend reading Benefits of Tall Grass on our website.
Many fertilizers push the lawn to grow vigorously and this can cause the lawn to stress during the hottest times of the year. It’s recommended not to fertilizer turf areas from mid-July to mid-September
Mow the turf area before the hottest parts of the day (usually before 3pm or after 7pm).