June 22, 2007

Freeze-damaged wheat Figure 1 (above, left): Wheat head showing slight frost injury (discolored awn tips), but overall, wheat kernels are light green and appear to be developing well. Figure 2 (above, right): Moderate frost injury as typified by damaged (non-green) awns and glumes with small kernels that appear to be ripening early. Figure 3 (left): A wheat head that has lost its green color because it is maturing. The kernels are all there and n the soft dough stage. The early ripening is probably due to recent hot, dry weather. (UNL IANR Photos by David Ostdiek)

With this year's disease- and freeze-damaged winter wheat, growers may need to make adjustments at harvest.

Bob Klein, extension crops specialist at the West Central REC in North Platte, noted that heads in some fields may be extremely fragile, which can increase shattering. Harvest those fields first that are most susceptible to shattering or where heads may have already started to shatter, Klein said. He also recommended slowing down reel speeds to reduce shattering during combining and adjusting combines to blow out as much lightweight seed and chaff as possible to reduce dockage. This will help improve test weight.

Fields that may have seed not acceptable or subject to discounts at the market due to disease or weed problems should be harvested separately from other fields, Klein said, to avoid further contamination. Also, clean out combines, grain carts, trucks, etc. as necessary when moving between problem and non-problem fields.

Paul Hay, extension educator in Gage County in southeast Nebraska, also recommends adjusting the air on the combine so lighter kernels can be blown out with the chaff. Typically wheat heads suffering from scab will be light in weight and color and may even have a hint of pink or salmon color if fusarium is present. Separating these lighter kernels can help reduce dockage at the elevator.

Typically speaking, when growers have situations that lower yields - such as freeze damage and leaf diseases - lower test weight wheat does not necessarily develop, Hay said; however, good rains at the wrong time, such as when the wheat is just ready to harvest, can significantly affect test weight.

If good weather conditions prevail, wheat harvest in Gage County is likely to start next week, Hay said. While wheat has had its share of problems this year, given the late spring frost and now an influx of diseases, it survives and produces a crop, living up to its reputation for having nine lives. Not many crops can do that as well, Hay said.