For:
By: Daniel E. Mullins
Extension Horticulture Agent
Dead Areas in Lawns Frustrate Gardeners
Area lawns are showing signs of problems again this spring. Though it is easy to blame those dead areas on our weather and sandy soils, the major cause is closer to home.
We diagnose hundreds of lawn problems each year and with only a few exceptions, most problems seen are caused directly or indirectly by mismanagement. This results in a slow weakening of the grass, making it more susceptible to weather extremes, diseases and other pests.
Following are the most common errors made in managing turfgrass.
■ Excessively heavy applications of fertilizer that result in extremely lush growth that is more susceptible to pest problems. On sandy soils, several very light applications spaced several weeks apart are recommended, instead of a single heavy application.
■ Daily watering that causes a shallow root system and allows fungus diseases to thrive. Water infrequently, but deeply. This encourages a stronger root system and less opportunity for infection by disease organisms.
■ An extremely low mowing height that slowly starves the lawn by not allowing enough leaf surface to manufacture food. Though low mowing yields a neater appearance, the result is stressed grass with a shallow root system that soon thins out and becomes weed infested.
■ Using a fertilizer that contains
high nitrogen and very little potassium creates an imbalance in the soil and
weakened turf. Current recommendations
call for a fertilizer with
■ Fertilizing in the fall with a
high nitrogen fertilizer that contains low levels of potassium can potentially
contribute to lawn winter injury. Signs
of winter injury are generally not seen until the following spring. Fertilization of centipedegrass should not be
done later than August in north
Question of the Week: I saw two adult mole crickets in my lawn this week. Is it time to apply an insecticide for
control?
Answer: Mole crickets seen in the spring are overwintering adults. They leave the ground at this time of year,
fly, mate and disperse to lay their eggs.
Treatment at this time of year is not advised. If treatment is warranted, wait until late
June or early July to apply an insecticide unless you plan to use the new
beneficial nematode product. Watch for a
future article concerning mole cricket control.