Potential economic benefits of adjusting dryland cropping practices based on seasonal rainfall expectations

The High Plains of Texas is classified as a semiarid area with an annual rainfall of 450 mm and an evapotranspiration ratio of less than 0.25. For the last decade, dryland yields for cotton, grain sorghum, and winter wheat production averaged approximately half of those for irrigated production systems. Conditions of high climatic variability coupled with frequent droughts account for the low crop yields obtained in this region.

Cropping practices that might be used to take advantage of seasonal rainfall conditions would include crop choice, planting density, planting date and fertilization. At present very little or no information is available to encourage High Plains dryland farmers to modify the cropping practices based on seasonal rainfall expectations. CroPMan simulation model was used to evaluate the economic benefits of using alternative management practices for dryland cotton, grain sorghum and winter wheat production. The top three producing counties in the High Plains of Texas were selected for the analysis of below and above normal rainfall conditions/scenarios. Stochastic Dominance with respect to a function (SDRF) was used to introduce risk and take into account of inherent variability of dryland production systems. Expected net revenues above variable costs were compared for the selected crops across management practices.

The results indicated that modifying cropping practices under below normal rainfall conditions would save a dryland cotton farmer in the range of $12 to $22/acre. Increased expected net revenues above variable costs for cotton production under above normal rainfall conditions were found to be in the range of $10 to $25/acre. The economic benefits resulting from adjusting grain sorghum production practices were found to be from $7 to $21/acre and from $3 to $5/acre under below and above normal rainfall conditions, respectively. The results for winter wheat showed that modification of cropping practices based on seasonal rainfall expectations would benefit a dryland winter wheat farmer in the range of $14 to $16/acre under below normal rainfall conditions. The expected profits for winter wheat production under above rainfall conditions were found to be from $11 to $20/acre. Results from this study reveal that dryland farmers would clearly benefit from modifying cropping practices based on seasonal rainfall expectations.