CROPS
By Dr. Paul Tracy

Reflections on the freeze and this year’s wheat crop

This spring, we had warm temperatures for several weeks followed immediately by sub-freezing nighttime temperatures lasting 6 to 7 days. The freeze affected the entire wheat crop across our region.

What followed the freeze was an interesting mix of agronomics, economics and social interactions. MFA’s corporate, area and local agronomists met with hundreds of producers representing thousands of acres. The effort was also supported through our grain division, feed division and corporate legal services. We also used an external agronomy network, with special efforts provided by the University of Missouri and Kansas State University.

The conventional wisdom was that wheat in advanced growth stages is the most susceptible to freeze injury. This was not always the case. We had some wheat in the boot stage that put out greater than 75 percent viable heads. We also had some wheat at early tillering that had frozen lower stems and excessive lodging.

Overall, we experienced projected wheat damage ranging from 10 percent to 100 percent loss. We often witnessed this injury across adjacent wheat fields of similar management. One thing we always learn from these types of events is that all fields must be evaluated individually!

What recommendations did we make concerning freeze-damaged wheat management? Growers had the option of destroying the stand and planting another crop, using the wheat as a forage resource or letting it mature to see what happened.

In most situations south of I-70, the wheat was damaged enough that many growers bought back their existing wheat contracts. This provided the lowest potential financial loss.

After making marketing decisions, we advised patience. The early reaction was to destroy wheat and immediately plant corn. From an agronomy point of view, I did not feel this was the best option for several reasons. First, the time window for optimum corn planting was rapidly approaching. Our experiences have been it is extremely hard to kill stressed wheat. A few weeks of active wheat growth is required following a frost for glyphosate to work effectively. Paraquat and other contact herbicides (with or without atrazine) generally do a poor job of killing stressed wheat. They rarely provide enough coverage to reach newly emerging tillers.

Planting corn into a mat of freshly decaying material often leads to stand problems. Disking does not offer the best residue management, and no one owns a plow anymore. Many folks simply sprayed glyphosate and planted glyphosate-tolerant corn. It’ll be interesting to see how those programs worked.

For most fields, we recommended following aborted wheat with soybeans. This allows more time to evaluate damage. Double-crop soybeans were initially planned following wheat. Soybean seed was much more available than corn seed prior to the freeze. Additional pressure was put on corn seed availability due to replants caused by the freeze at locations where corn had emerged.

Many growers elected to use the winter wheat as a feed resource. This was a good option because it dealt with the green residue problem and still allowed time to put in a soybean crop. Winter wheat makes good forage, whether it is grazed, bagged, ensiled or hayed. The fact that the region is critically low in forage feedstocks and that our pasture and hay crops were also adversely affected by the frost made using wheat as forage a viable option.

There were a few roadblocks associated with using wheat as forage. Stressed wheat commonly contains high levels of nitrates, which can be toxic to ruminant animals. Initial tests showed our freeze-damaged wheat contained high nitrates. By late April, nitrate numbers had dropped but were still high. Based on this information, we advised waiting before haying or grazing to allow the wheat to convert nitrates to proteins.

We recommended bagging or ensiling any wheat that needed to be harvested immediately after the freeze. The ensilage process eliminates approximately 50 percent of forage nitrates. Also, in April, weather conditions are not often conducive to quality hay drying.

Another key issue with feeding was that some of the herbicides used in winter wheat were not labeled for animal feeding purposes.

It is still too early to tell the full extent of the freeze (early May press time), but I thought it would be fun to give a summary of our experiences and recommendations for the 2007 wheat crop before 20/20 hindsight kicks in. Let us know how things turned out.

How did you respond to the freeze? What marketing and management decisions did you make? Were those choices successful? Where did you get the information used to help make those decisions? I will keep correspondence confidential, but I will try to summarize your experiences into a Today’s Farmer follow-up. Send comments via email (preferred) or mail to:

Dr. Paul Tracy
MFA Incorporated
201 Ray Young Drive
Columbia, Missouri 65201
ptracy@mfa-inc.com  

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