Back Page News from USDA Crop Report 
        By now, most people have either seen or heard about the January crop report from USDA and the record high projections of yield and production for corn and soybeans.  Also included in the report were a few other interesting tidbits.  Let's start with winter wheat.  Nationally, acres planted to winter wheat last fall totaled 37.1 million acres, down 6.2 million acres from a year ago.  This is the lowest seeded acreage since 1913.  Further, there is a 29 percent drop in the number of seeded acres to soft red winter wheat (the type grown Wisconsin).  In Wisconsin, winter wheat seedings decreased 85,000 acres from 335,000 in 2008-09 to 250,000 acres in 2009-10.  The late fall grain crop harvest really impacted wheat plantings.  Expect most of the lost wheat acres to be planted to corn or soybeans next spring. 
        Also included in the crop report is what USDA terms "Objective Yield Data" for corn.  This is essentially a count of the number of ears per acre determined from randomly selected fields.  In essence, this is the planting rate less seeds that didn't germinate, seedlings that didn't develop into productive plants, and barren plants.  Added to this number would be plants with multiple productive ears.  The below graph shows final ears per acre for selected states. 

         Wisconsin corn producers ranked fourth behind MN, IA, and IL.  A final ear count of 28,100 indicates that most producers are seeding at or just above 30,000 seeds per acre.  This is about the minimum of where final stands should be. v

Nutrient Watch List
        At the recent Wisconsin Crop Management Conference, Carrie Laboski, UW Extension Soil Scientist, offered a presentation entitled "2010 Nutrient Watch List."  She made the point that much attention is focused toward nitrogen and phosphorus because of their environmental impacts and, because of this, not enough thought may be given to other nutrients.  Two nutrients with increasing agronomic significance in Wisconsin are potassium (K) and sulfur (S).

Potassium
        Although potash prices have decreased somewhat, they remain high compared to historical values.  High prices often lead to reduced applications.  In 2009, the number of alfalfa samples submitted for plant analysis to the UW Soil and Plant Analysis Lab (SPAL) and testing below optimum for tissue K more than doubled based on a percentage of samples analyzed (about 40% compared to 16% in 2008).  Instances of K deficiency in corn and soybeans are also on the increase.  As a macronutrient, K is needed in relatively large amounts, especially for alfalfa and corn silage.  Deficiencies will result in significant yield reductions.  Keep in mind that manure is an excellent source of K but must be applied and allocated properly. 

Sulfur
        Historically, a major free source of sulfur (as sulfate) has come from atmospheric deposition (a.k.a. industrial air pollution).  The Clean Air Act of 1970 has resulted in significantly less sulfate being deposited on the land base.  Currently, the Fond du Lac area has about 9 lbs/acre deposited compared to more than double that amount twenty years ago.  As with K, many more plant analysis samples are turning-up deficient for sulfur.  In fact, 85% of alfalfa tissue samples submitted to SPAL as abnormal in 2009 were low in sulfur; while 44% of the normal samples were deficient.
        Sulfur deficiency is most likely to be a problem in fields with low organic matter, fields that do not routinely have manure applied, or fields with low subsoil sulfur.  Like K, alfalfa has a relatively high demand for sulfur. 

Bottom line:
        Pay attention to K and sulfur field or plant nutrient levels.  Verify nutrient deficiencies with a soil test and/or plant tissue analysis.  Not all fields are deficient, but deficiencies for these two nutrients are becoming more common. v