Timing Is Everything February 27, 2015

Timing Is Everything

Poa Annua Flowering Is A Sign Of Spring

By Keith Happ
March 17, 2009

Recent weather patterns have been encouraging, and warmer weather has allowed the frost to melt in the soil profile. Conversations with many superintendents confirm that soils are no longer frozen, are drying, and turf growth is just beginning. Calls from the southern portion of the region focus on Poa annua seedhead suppression while conversations with superintendents in the north center on smoothing the playing areas in anticipation of the first mowing of the year.

Spring Turf Growth

A key factor for turf growth is soil temperature. As the days continue to get longer, soil temperature will increase, the ground no longer freezes at night, and the sun rises higher in the sky. Some level of turf growth should occur before programs are implemented to manipulate playing conditions. Forcing a turf response at this time of the year will compromise turf health during this period of emergence from winter dormancy. Golf can be played, but golfers should not expect mid-season conditions this early in the year. It is still winter despite the fact that the clocks have been moved ahead.

Two approaches can be used as indicators of Poa annua seedhead emergence. One strategy is to physically examine the turf to determine if the seeds (flower) is in the boot or base of the plant. The Poa annua seedhead can be felt in the stem of the turf plant. Pulling apart individual Poa annua stems is a tedious and time consuming task.

A second strategy is to use a Growing Degree Day (GDD) model. Two different models are used with this method; the 32 and 50 degree Fahrenheit models. The 32 o F GDD model works well in the upper elevations and the northern tier of the region while the 50 o F GDD model can be used in the south. When using the 32 o F model an accumulation of 400 to 450 GDD is an indicator to initiate seedhead suppression methods, and an accumulation of 50 GDD is required when the 50 o F model is used. If you use one of these models, be patient. Treating too early may not deliver the best control of seed emergence; however treating too late also can compromise results. If you have questions about these models, give us a call.

Economics and Turf Care

Several calls have been received inquiring about information on cost cutting measures. Many cost cutting ideas relate directly to the course preparation. If resource allocations have changed it is unrealistic to expect that the course can be prepared exactly as it has been in the past. Ideas for savings can be discussed during a Turf Advisory Service visit. All areas of course maintenance can be discussed along with the potential ramifications on playability when maintenance programs are changed. Remember, our Green Section visits can focus on these and other cost cutting and efficiency matters.

Always remember, the Mid-Atlantic Region agronomists are part of your agronomic support team. If you have a question or concern, give us a call or send an e-mail. Stan Zontek ( ) and Darin Bevard ( ) at 610/ 558-9066 or Keith Happ ( ) at 412/ 341-5922.