Farm Talk

August 7, 2012

Tips for maximizing wheat yields


Parsons, Kansas — With wheat planting coming around the corner, Phil Needham has some ideas on how farmers can make the most of the 2013 wheat crop, even in drought conditions.

Speaking at the Bayer CropScience ProfitMaximizer Wheat Summit in Wichita Aug. 1, Needham—who owns Needham Ag Technologies, a crop consulting firm that emphasizes intensive management in wheat - says maximum wheat yields begin before the first seed is placed into the ground.

Choosing the best seed varieties for a farmer's given farm and management system is critical. Look carefully at university yield trials and select varieties based on several years of yield history. Needham recommends choosing at least three varieties to plant.

Top-quality seed should be cleaned over a 6/64 screen, preferably on a gravity table. University data shows that larger seed results in three- to five-bushel per acre yield increases over smaller seed. Having seed that is uniformly sized improves emergence uniformity, says Needham, who encourages farmers to have seed checked for germination and vigor at a certified seed laboratory.

Beating the fall infestations of insects requires the seed be treated with insecticide and fungicide, which improves fall plant health at the pivotal germination and stand establishment phase. A seed treatment also helps ensure stand uniformity, which Needham says is a critical step in obtaining his goal of 500 to 600 heads per square yard at harvest. Typically, that means shooting for about 300 plants, each with one or two tillers.

Planting into a seedbed free from weeds and volunteer wheat is important. Not only can weeds rob moisture, but volunteer provides a haven for the bird cherry oat aphid, a vector for Barley Yellow Dwarf. Needham says BYD was a tremendous yield robber in Kansas fields in 2012. The tiny aphids can reproduce quickly, so producers need to scout field diligently. Thresholds of five aphids per square foot merit treatment with a fungicide application, although insecticide seed treatments can provide control for several weeks after planting.  

Knowing the number of kernels per pound is important, as seed size can vary greatly. Many farmers routinely use 14,000 seeds per pound as a rule of thumb. To obtain Needham's goal of 300 seeds per square yard would require planting 103 pounds of seed per acre. However, counts of 11,000 or 17,000 per pound would require 132 and 85 pounds of seed per acre, respectively—a dramatic difference in planting rates.

Needham suggests farmers need to apply phosphorous fertilizer with the seed. Whether liquid or dry makes no difference, although liquid fertilizer in the seed slot needs to "stream" on rather than drip. A fertilizer orifice that drips will skip several inches in each foot of row, making it more difficult for a young wheat plant to use that fertilizer early on.

For farmers planting wheat into failed corn this fall, Needham says to be wary of adding additional nitrogen. Many of these corn fields have plenty of residual nitrogen, which will result in tall wheat plants and could cause lodging prior to harvest. Farmers may wish to limit or even eliminate additional nitrogen applications to keep these fields from lodging.£