Careful planning can minimize wheat growers' drought pains
By D. Chad Cummings
Ph.D., Field Research Scientist, Dow AgroSciences
Growers across the United States face many challenges each year, although none may be as great as the recent drought conditions. Unfortunately, the U.S. Seasonal Drought Outlook predicts that drought conditions will continue to “persist or intensify” for states throughout the Wheat Belt,though recent beneficial rains are helping some of us head in the right direction. Careful planning and monitoring can offset the drought impacts.
This recent drought began in summer 2011, and southern Plains states experienced the driest conditions. Although there was some relief in spring 2012, most of the Midwest is now experiencing extreme drought too.
A big concern is the long-term loss of water in ponds and streams across states such as Kansas, Nebraska and Oklahoma. Growers are experiencing a loss in surface water available for irrigation, especially for use on summer crops. When possible, growers are using water from the Ogallala Aquifer, but others must simply wait for rain. Most regions need more than their annual average precipitation; in some places, they need an additional 6 to 9 inches to generate full recovery. Wheat farmers who planted in early fall 2012 benefited from some timely rains. Those who waited or had to finish harvesting a summer crop are at a disadvantage this year. Snow and spring rains, they hope, will make up for that missed moisture.
The drought also indirectly affects herbicide application. As growers look to optimize chemical weed control, adjustments to herbicide usage are important, especially during prolonged drought. Labels for both postemergence and soil residue herbicides indicate that the plant needs to be actively growing to take in the active ingredient either through leaves or roots. When no moisture is available for the crop to grow, there is virtually no water for weeds either. Any amount of precipitation can be enough to stimulate growth for the crop and the weeds.
Growers and agronomists should prepare to be flexible. Plan herbicide applications during a drought according to moisture and plant growth signals, not specific calendar timing. Choose a herbicide with a wide application window so it can be applied when grass and weeds do start to grow—preferably until wheat jointing, which is important when growers have to wait for later rains in the spring.
Top-dressing also is a common practice for wheat growers in the spring. Growers apply nitrogen fertilizer to benefit the crop. Time fertilizer applications around active growing conditions when there is adequate moisture for true growth. Fertilizer burn can inhibit growth in a normal year, and drought conditions only compound the problem. Some herbicides may be mixed with a top-dress application. Producers and applicators should consult individual product label for best management application recommendations.
If the precipitation doesn’t come or if winter wheat crops fail, producers still can take proactive steps to improve their soil nutrients before planting a summer crop. Take advantage of soil testing to evaluate fertility for the next crop. It is important to make adjustments in pH and nutrient levels early to optimize the soil conditions.
Ultimately, drought conditions mean that growers must know their fields. Create opportunities even during these dry times by tracking growth, monitoring moisture and planning ahead for soil fertility.