Kelly J. Bryant

THE VALUE OF IMPROVED ENSO PREDICTION TO U.S. AGRICULTURE

The economic value of long-range weather prediction is measured by the increase in social welfare arising from the use of the prediction in economic decisionmaking. This paper describes a study of the economic value of ENSO prediction to U.S. agriculture. The interdisciplinary study involved the analysis of data and models from meteorology, plant science, and economics under a framework based on Bayesian decision analysis. The estimated annual value of perfect ENSO prediction to U.S. agriculture is

Impact of ENSO-Related Climate Anomalies on Crop Yields in the U.S.

323 million.

An Intraseasonal Dynamic Optimization Model to Allocate Irrigation Water between Crops

Historical daily thermal and precipitation data from selected stations across the United States are composited into climate scenarios for the three phases of ENSO: Warm Events (El Niño), Cold Events (El Viejo or La Niña), and Neutral. Using these scenarios, yields of 7 field crops were simulated using the EPIC biophysical model during the one-year period coincident with maximum SST anomalies in the equatorial Pacific. The response of simulated agricultural productivity to the ENSO-related climate-variability parameters, is presented. A sensitivity calculation confirms the relevance of precipitation totals/medians and suggests ENSO-related yields are sensitive to changes in statistical properties characterizing precipitation distribution and occurrence. Results are spatially dependent, with the southwest and northern plains regions indicating the highest sensitivity to the inclusion of additional precipitation characteristics. The southeast yields are not as sensitive. The yield deviations (expressed as normalized differences to neutral yields) associated with the two extreme ENSO phases (Warm Events and Cold Events) are spatially and crop dependent with ranges up to ±120%. The largest yield deviations are in the south, southwest, and northern plains. Overall, Cold Events demonstrate larger impacts in the southern regions and Warm Events have a larger impact in the north. Additionally, the notion that climate anomalies associated with Cold and Warm Events and subsequent impacts on yields should be of opposite sign (i.e., linear) is not valid in many regions. For the eastern half of the U.S., modeled yield deviations under Warm Event conditions are nearly all less than neutral. Conversely, in the western half, results are more mixed. Under Cold Event conditions, yields in the east are enhanced in the south, but worsened in the north; while in the western half, yields have decreased in general. The results highlight the critical role of climate and production-related data on station or county levels in quantifying the impact of ENSO climate anomalies on yields. Both the diverse nature of the ENSO-related yield deviations as well as their sensitivity to monthly frequency distribution and occurrence characteristics imply that ENSO-related seasonal precipitation forecasts might be beneficial for agricultural application only if details were provided regarding not only totals, but also predicted changes in temporal and spatial variability of a more comprehensive suite of characteristics.

Valuing Transgenic Cotton Technologies Using a Risk/Return Framework

A dynamic programming model that allocates irrigations among competing crops, while allowing for stochastic weather patterns and temporary or permanent abandonment of one crop in dry periods, is presented. Fifteen intraseasonal irrigations are allocated between corn and sorghum fields on the southern Texas High Plains. Broad rules of thumb implied by the results suggest irrigating the driest field in any stage unless soil water is close to field capacity on both fields or below wilting point on corn. A crop simulation model is used to reduce the complicated decision rules into simpler strategies with similar net returns.

Maize Growth and Yield Response to a Biostimulant Amendment

Stochastic Efficiency with Respect to a Function (SERF) is used to rank transgenic cotton technology groups and place an upper and lower bound on their value. Yield and production data from replicated plot experiments are used to build cumulative distribution functions of returns for nontransgenic, Roundup Ready, Bollgard, and stacked gene cotton cultivars. Analysis of Arkansas data indicated that the stacked gene and Roundup Ready technologies would be preferred by a large number of risk neutral and risk averse producers as long as the costs of the technology and seed are below the lower bounds calculated in this manuscript.

Performance by Heifers Grazing Sod-Seeded Cool-Season Annuals Seeded on Different Dates Using Two Tillage Intensities

ABSTRACT Various companies are marketing biostimulant products with claims of higher yields and improved quality. Greenhouse and field experiments were conducted from 2010–2013 to determine the influence of Foliar Blend® (FB, Agri-Gro Marketing, Inc., Doniphan, MO), a chelated micronutrient/biostimulant amendment, on the growth and seed yield of maize (Zea mays L.). When applied pre-emergence and again at V5 growth, greenhouse-grown maize seedling heights and leaf area increased at 2.34 L FB/ha or greater and root and shoot dry matter increased at 7 L FB/ha compared with untreated plants. In field studies, maize yields increased at 2.34 L FB/ha or greater in 2011. In 2012, yields improved with FB but not significantly. Primary ear heights at 1.2 L FB/ha and 2.34 L FB/ha were greater than the control in 2011 but not in 2012. We conclude that FB can alter maize growth, but yield responses are inconsistent and possibly related to environmental interactions.

VALUE OF IMPROVED LONG-RANGE WEATHER INFORMATION

A total of 120 Gelbvieh × Angus crossbred heifers (552 ± 2.5 lb initial BW) grazed pastures of common bermudagrass [Cynodon dactylon (L.) Pers.] overseeded with wheat (Triticum aestivum L.) and annual ryegrass (Lolium multiflorum Lam.) for a 3-year study to compare the effect of seeding dates and tillage intensities on heifer growth performance. Half of the pastures were seeded in early September (Early) and half in mid October (Late). Within seeding date, half of the pastures were disked once (1×) and half were disked twice (2×) before seeding. Grazing began when forage mass reached approximately 2000 lb/acre and continued through 11 May 2002 (year 1), 25 April 2003 (year 2), and 10 May 2004 (year 3). Forage mass was greater from Early than from Late seeded pastures for 2 of the first 3 months of grazing resulting in 17-day earlier grazing initiation and approximately 165 lb less hay fed per heifer. Total body weight gain, or gain while grazing cool-season annuals did not differ between seeding dates or tillage intensities. Producers in the Mid South region with bermudagrass pastures may have considerable flexibility in their decisions as to when to seed annual forages and to what intensity they till their sod depending upon how soon they need available forage.