Wheat cleaning practices of U.S. commercial elevators - report derived from survey of grain elevator managers by National Grain and Feed Association - U.S. Dept. of Agriculture, Economic Research Service report

Situation and Outlook Report: Wheat, Nov, 1991 by Brian Just, Kristi McComas, Mark Ash, Bengt Hyberg

Elevator Cleaning Capacity

Sixty percent of all wheat elevators in the sample had grain cleaning equipment (A-5). County elevators had by far the largest share (67 percent) of the reported wheat cleaning capacity. A higher proportion of export elevators had

grain cleaners, but country elevators cleaned relatively more grain handled. Although 36 percent of the river elevators indicated that they had grain cleaners, none reported that they had regularly cleaned wheat. The survey data indicates that elevators cleaned about 10 percent of wheat handled. Average operating capacity per elevator averaged 5,424 bushels per hour. Many of the elevators indicated that they did not approach the manufacturer's rated capacity for the cleaner. Elevators with cleaners had hourly operating capacities averaging 57 percent of their total hourly loadout capacity. The survey suggests that the rate that terminal and export elevators operated their cleaners relative to their loadout capacity was generally lower than country elevators.

Potential Added Cleaning Capacity

The survey showed that 36 percent of all respondents could install or increase the grain cleaning capacity within their current facility. The average capacity increase was 6,740 bushels per hour. Of the sample respondents, 72 percent indicated that the cost to increase cleaning capacity would be less than $100,000. However, half of the elevators with storage capacity exceeding 5 million bushels reported that they could only increase cleaning capacity at a cost exceeding $100,000. Assuming a workload of 700 hours per year times 233 elevators (36 percent of 646 wheat elevators), the survey indicates a potential to add 1.1 billion bushels to annual cleaning capacity. A greater proportion of the river elevators (57 percent) indicated an ability to increase capacity.

Cleaning the Classes of Wheat

Other observers have noted that if grain quality is usually good in an area, elevators are less likely to discourage patrons by discounting for dockage unless it is a widespread practice (3). The average dockage received by elevators that purchase on a gross weight basis is 0.9 percent, compared with 1.3 percent for elevators taking a weight deduction. Winter wheat elevators receive wheat that has less dockage on average than elevators taking spring wheat. This can change for any given year, however, due to weather conditions. The average level of dockage received by elevators was 1.0 percent for winter wheat and 1.85 percent for spring wheat. Therefore, proportionately fewer elevators in HRW regions discounted dockage. Country elevators reported receiving higher-dockage wheat than export elevators. Average dockage levels for wheat of the reporting elevators declined from about 1.2 percent to under 0.5 percent as it moved through the grain marketing system. The range in dockage levels was also greater at country elevators. The average foreign material percentage also declined from 0.55 to 0.35 percent. There are several possible explanations for this outcome. First, elevators along the marketing channel reduce the average levels of dockage and foreign material through cleaning and blending. Second, country elevators sell the high-dockage wheat to the feed market. Third, some wheat importers may specify lower factor levels in their contracts than domestic wheat millers. Elevators handling hard red spring wheat cleaned more often than those handling other classes. The following data excludes cleaning for seed wheat. About 60 percent of the spring wheat elevators cleaned compared with 17 percent of elevators handling winter wheat (A-6). This probably is a result of the differing harvest practices and weather conditions (5). Spring wheat is often windrowed prior to harvest. While this permits quicker drying and speeds harvest, the use of a windrow pickup header inevitably collects soil, weeds, and other trash with the wheat. Winter wheat generally dries naturally and is straight combined, resulting in delivery of less dockage and foreign material to elevators. FGIS inspection data for the 1986-90 wheat crops reported average dockage levels for HRW, SRW, and HRS at 0.86, 0.85, and 0.94 percent, respectively.