Wheat, oats, triticale and rye are common small grains produced in Georgia for grain, grazing or cover. As I have traveled around the state this past January, it was obvious that early planted grains had taken advantage of the warmer conditions in the fall to produce much growth. Wet conditions as of late, have reduced available nitrogen supply and slowed vegetative production. The cold wet conditions have had their negative effects on basically all the small grains particularly those fields planted in December. Late planted small grains haven’t had enough time to accumulate growth under these conditions. Cloudy, cold conditions generally reduce growth rate and undermine the yield potential of the crop. In wheat, fall tillering generally accounts for about 85% of the yield.
Late planted wheat is suffering the most in regards to tiller production. It will take a much cooler spring for late planted fields to have a chance to make good yields due to such poor chances of good dry matter accumulation. Usually, I consider about 30 lbs of N to be a good approach to supporting tiller growth and avoiding over fertilization in the spring. There are two charts in the Georgia Wheat Production Guide that can help determine how much nitrogen to apply depending on your tiller rates. In addition, North Carolina State and Virginia Tech provide similar guides on line as well. I encourage you to look at these on line publications.
As we get into February, consider an additional application of nitrogen on late planted small grains to encourage tillering prior to the warmer temperatures particularly in north Georgia. In addition, now is the time to make sure ryegrass and wild turnips and radish are controlled before spring green up. By green up, weeds will be much more difficult to control.
In the southern counties, many of the fields that were planted in timely order will soon be entering into a reproductive phase. At this stage it is best to make the remaining nitrogen applications to ensure that the developing grain heads have ample supply of nutrients to form high yielding heads. As stem elongation proceeds, responses to nitrogen applications lessens so take the opportunity when fields conditions allow you to put equipment in the field and apply your nitrogen. In addition, I strongly discourage the use of a herbicide once the wheat grain head or other grains begin developing in the culm as herbicides such as 2,4-D and/or Dicamba can severely injured your yield potential.