Over the last couple of days I have received a few questions concerning wheat. Below are some thoughts about early season wheat production and how those decisions can affect yield.
Planting Dates: According to the 2017/18 UGA Wheat Production Guide. The optimum window for wheat planting in Georgia is typically within one week before or after the average first frost date for a given area. Planting during the appropriate time for your area will allow wheat to develop enough tillers prior to January or early February which reduces the likelihood of needing two applications of N fertilizer in the spring. Fall produced tillers will have stronger root systems, tolerate more stress, and produce larger heads with greater potential for high test weight. Studies show that fall tillers account for about 85% of the yield. If the crop is planted late and plants do not tiller well prior to the onset of winter days, then the crop will be dependent of spring tillers. Spring tillers generally have smaller heads, fewer spikelets and less opportunity to produce grain.
Seeding rates: Some area growers establish wheat by broadcasting and incorporating with a disc or do all. In general, establishing wheat by using a drill increases yields by 7 to 8% when comparing to broadcasting. If using a grain drill, the seeding rate of wheat needs to be around 22 to 25 seeds per row foot (7.5 inch drill width). This is equivalent to approximately 35-40 seeds per square foot. If you are planting during the late side of the planting window then bump up the seeding rate by 10 to 15 percent. Wheat emerges best when planted 1 to 1.5 inches deep. When broadcasting seed, calibrate the equipment to plant 40 seeds per square foot.
Growers sometimes ask about how many pounds of wheat seed to plant. Well, it all depends. In a normal year, wheat cultivars vary between 10,000 and 18,000 seeds per pound. The difference in seed size can impact the actual seeding rate if a grower goes by bushels per acre instead of seed per foot.
Nitrogen Management: Nitrogen should be used in the fall or at planting to encourage tiller production prior to the onset of winter. Tillers produced in the fall generally produce the most grain per unit area. It is important not to over apply nitrogen at this time because this may cause excessive growth and result in winter injury.
In general, apply at plant N (based on the previous crop rotation) as follows:
Cotton: 35 to 40 lbs ac
Corn: 30 to 35 lbs ac
Fallow: 25 to 30 lbs ac
Soybeans: 15 to 20 lbs ac
Peanuts: 0 to 15 lbs ac
What about poultry litter for wheat production? For wheat, an application of 2 ton/a of poultry litter (preplant incorporated) will supply an adequate amount of fall N and should meet the P and K requirements of even if your soil test level P and K are low. The remainder of the N requirement should be applied in the spring using commercial N fertilizer. Consider getting your litter tested to determine nutrient content because nutrient levels can be variable. On average, broiler litter contains approximately 3 % N, 3 % P2O5 and 2 % K2O (fertilizer value of 3-3-2).
Weed Control: Wild radish control in small grains has been a common question from area growers. Below are recommendations from Stanley Culpepper concerning ryegrass and wild radish management in wheat.