This year has not been the best for wheat in Georgia. According to the Intensive Wheat Management in Georgia publication, for high wheat yields it is desirable to obtain 50 to 70 heads per square foot. To achieve this, there has to be enough nitrogen for wheat to develop 80 to 100 tillers per square foot prior to stem elongation.
So, late January has been one of two very important weeks in the life of this current crop. A Georgia producer's goal is to have around 70 or more tillers per square foot of planted wheat. On 7-inch rows this equates to 70 tillers per 20 inches of row. Growers should take a ruler or tape and measure 20 inches of row and count the tillers. A lot of wheat fields do not have tiller counts this high in west-central Georgia.
If the field does not average 70 tillers per 20 inches across several spots in the field, apply 30 to 40 pounds of nitrogen immediately. With recent rain, the window for splitting nitrogen is closing.
Those who do split applications of nitrogen can wait an extra week or two before making a final application. Generally, growers should apply nitrogen in the first or second week of February so that the plants will have adequate nitrogen prior to stem elongation. (When stem elongation is occurring the plants that are now flat and running along the ground will begin to grow in an upward manner.)
By split applying the nitrogen, the grower gives the plant adequate nitrogen at stem elongation and, therefore, can wait until the third or early fourth week of February to make the final application.
If a grower makes split applications, how much nitrogen should he apply in February? Add up the nitrogen applied at planting, plus the nitrogen applied in January, and subtract this number from the total amount of nitrogen planned for the crop.
For expected yield goals of 40 to 70 bushels, use a total nitrogen rate of 80 to 100 pounds. For 70 plus bushels use a total nitrogen rate of 120 pounds per acre.
Remember to adjust for the preceding crop. If following peanuts or soybeans decrease the nitrogen rate by 20 to 40 pounds per acre. If following grain sorghum or cotton, increase by 20 to 40 pounds per acre.
Growers also need to look at the weed spectrum in their wheat fields. For henbit, Harmony Extra would be a good choice. Wild radish must be small (less than 3 inches diameter) for adequate control with Harmony Extra. For wild radish, Express + MCPA and 2,4-D are usually the most effective options but consider the size and growth stages of the wheat crop.