COURSE CARE
Let’s Talk Spring For A Change March 31, 2014 By Elliott L. Dowling

Basing agronomic designs solely on the calendar may cause you to misjudge timing of critical applications for Poa annua seadhead suppression and annual bluegrass weevil control. Even though the calendar says its time, the turf will tell you if it is ready or not.

By now we are all tired of snow and cold weather. Finally, warmer days have arrived along with a few spring rain showers. Hopefully by now everyone has evaluated any potential damage that resulted from winter. Indications are that damage is relatively limited throughout the region, which is excellent news.

Course cleanup and spring core aeration treatments are the primary focus. Superintendents are behind schedule because of the extended winter weather delays but are now taking advantage of warmer, sunny days. Expect maintenance crews to work longs hours for the next few weeks to play catch up.

Phone calls are coming into our office regarding Poa annua seedhead suppression and what is the best timing for initial applications. This year, the question of when to apply is difficult to answer. Normally, the winter follows a somewhat predictable pattern leading into spring. This allows us to use historical data and growing degree-day (GDD) models to predict when preventative applications should be made. This winter has been anything but predictable. Monitoring your turf will be the best approach for timing seedhead control applications. Remember, you are looking for seeds in the boot stage. Once you see the Poa annua plant sheath swelling, this is the indicator that timing is right for applications. Additionally, use other Poa plants on the course as indicators. For instance, if you notice seedheads on fairway turf, expect seeds on your greens in the near future.

Like monitoring for Poa annua seedheads, the same holds true for annual bluegrass weevil control. Scouting is your best method to determine timing of control applications. Once warmer days are upon us, adults will begin to move. Other indicators, such as half green/half gold forsythia, can help determine when applications should be made. Remember, the goal is to control female adults before they lay eggs, not the instant they emerge.

Treating for Poa annua seedheads and/or annual bluegrass weevil because the calendar tells you to is not likely the best approach this season. Keep in mind, both of these nuisances adapt to changes in the environment, not the calendar. To be successful, we too must adapt. This year more than usual it is important to get into the field for firsthand observations to best time control applications.

Source: Elliott L. Dowling (edowling@usga.org

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