The Food Journal and Food, Nutrition & Science

An alliance between The Lempert Report and The Center for Food Integrity

Drought Effects Winter Wheat Crop

Drought Effects Winter Wheat Crop

Climate and Crops

March 29, 2009

Last year, a wet harvest in the United Kingdom dropped protein levels more than a percent in their wheat. The consequential reduction in the supply of higher quality wheat caused a rise in the price of bread flour. Now, domestic weather patterns may produce some similar price results.

Although most of the winter wheat areas are free of snow cover, and growing delays are not anticipated, the severe drought that set in starting in November, 2008 – combined with above normal temperatures – has caused nearly 20% of Kansas wheat to be rated poor-to-very poor as of the latest assessment. 

While cooler and damper conditions in the early growth would be ideal, any drought-busting rains that may occur in the months to follow may be detrimental to the wheat crop. Wheat relies on the sun for photosynthesis as it provides carbohydrates to fill the grain. Wet weather (during June and July) would delay the harvest and could lead to powdery mildew and fusarium – fungi that hurt wheat quality and yield. Some rain is, of course, needed throughout the growing processes, but there needs to be a fine balance between too much and too little.

In September and October of 2008, wheat was planted in the Midwest and Southern Plains. Before the winter freeze set in, the crop sprouted and then became dormant. As the soil now warms, the wheat will grow, taking on a grass-like appearance. By late April, heading should begin, as the crop takes on a more traditional appearance.  

Unfortunately, the Storm Exchange World Climate Service Spring climate forecasts the warm and dry conditions to persist into May over the Southern Plains. With some portions of Kansas, Oklahoma, and Texas seeing less than 20% of normal rainfall over the past 90 days and no significant rain in sight, wheat quality may continue to degrade.

To make bread, the optimum protein level is between 11.5 and 14%, which allows dough expansion and a sufficient density. The possibility of a late emerging crop as well as disease may lead to protein levels below 11.5%, resulting in poor quality wheat. However, subpar quality wheat can be used in the food making process when it is combined with wheat in better condition. 
Wheat quality is likely to have an effect on many foods found in the supermarket. Used heavily in flour and most baked goods, wheat is grown in 42 states in the U.S. More foods are made with wheat than any other cereal grain.