ON-FARM WHEAT STORAGE IN KANSAS: A DESCRIPTION, ASSESSMENT OF LOSSES AND A COMPARISON OF QUALITY MAINTENANCE COSTS UNDER VARIOUS PEST CONTROL STRATEGIES

Studies to describe the conditions under which wheat is stored on-farm in central Kansas and to compare the cost of pest control under various strategies with the cost of quality deterioration and loss were carried out. The most economically advantageous strategy of quality maintenance was sought.;When farm-stored wheat was sold, the likelihood that it would receive a price discount appeared to depend both on the number and type of insects present. About 70% of farm-stored wheat that would have received the "weevily" designation was discounted while 25.5% of other wheat was discounted. One-half of the observed discounts were ;The Standard Volume Weight (SVW) method of loss estimation was ineffective when used in Kansas farm-stored wheat. Apparently, the variability in dry bulk density within the masses of wheat was large enough that in many bins, losses of less than 1.2% could not be considered significant. It was shown that other loss estimation techniques would probably have been less effective than the SVW method under conditions of the study.;Protectant was a sound pest control investment in farm-stored wheat. In November, 1984, the ratio of total cost of pest control (weight loss, treatment and risk of discount) was 1 : 2.45 : 4.38 : 4.83 for protectant alone, no treatment, fumigation alone, and protectant plus fumigation, respectively. In February, protectant treatment cost ;A questionnaire survey of 148 randomly-chosen wheat producers showed a mean on-farm wheat storage capacity of 19,858 bushels. Sixty percent of farm bins were flat-floor round metal structures. Forty percent were aerated. A disproportionately large amount of on-farm storage capacity was held by a relatively few producers, while 45% of those who stored wheat on-farm had 10,000 bu or less. Application of protectant insecticide was the most common method of pest control, but fumigation was also common. Approximately 26% of producers who stored on-farm used neither protectant nor fumigation. This group stored less wheat for a shorter period of time than other groups.