Browsing by Author "Mullen, Jeffrey D."

Now showing 1 - 4 of 4
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    A Bio-Economic Model of Long-Run Striga Control with an Application to Subsistence Farming in Mali
    Mullen, Jeffrey D. (Virginia Tech, 2000-07-10)
    The parasitic weeds belonging to the genus Striga are among the world's most tenacious, prolific and destructive agricultural pests. Crop loss estimates due to Striga infestations can reach 100 percent. Furthermore, the weeds' affinity for low-fertility soils and low rainfall means that those farming the most marginal lands are most severely affected. Nonetheless, subsistence farmer have yet to adopt seemingly beneficial control practices to any appreciable degree. This paper develops a bio-economic model capable of identifying: (1) affordable, effective Striga control practices consistent with the resource constraints of subsistence farmers; and (2) barriers to the adoption of those practices. The model is comprised of two components: a biological component modeling Striga population dynamics, and an economic component representing the production opportunity set, resource constraints, and price parameters farmers face. The model is applied to two zones in Northwestern Mali, Sirakorola and Mourdiah, and solved using non-linear, dynamic programming. Data collected by the USAID IPM-CRSP/Mali project are used to specify the economic parameters of the model. A new technique for estimating the lower bound of a farmer's production planning horizon is also developed and employed in the application of the model to Sirakorola and Mourdiah. The results of several model scenarios indicate that the availability of information regarding the efficacy of Striga control practices is a primary barrier to their adoption by subsistence farmers. The movement of Striga seed between fields, however, is of limited importance. The "optimal control practices" identified by the model depend on the size and demographic composition of the production unit (UP), the zone in which the UP is located, and the cash budget available to the UP. At low budget levels, the model suggests planting millet without fertilizer at a high density in Sirakorola and a low density in Mourdiah. At high budget levels, the model suggests planting millet at a high density in both zones while applying urea. The benefits of adopting the optimal set of practices are presented in both nutritional and financial terms, and can reach as much as a ten-fold increase in the nutritional content of and financial returns to a harvest.
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    Economic evaluation of integrated pest management programs : a literature review
    Norton, George W.; Mullen, Jeffrey D. (Virginia Cooperative Extension, 1994-03)
    Integrated Pest Management (IPM) is an approach to making pest control decisions with increased information and the use of multiple tactics to manage pest popwations in an economically efficient and ecologically sound manner. The IPM concept emphasizes the integration of pest suppression technologies such as biological control, e.g., using beneficial organisms against pest organisms; cultural control, e.g., using rotations and cultivations to reduce pest problems; legal control , e.g., abiding by state and federal regulations that prevent the spread of pest organisms; and chemical control, e.g., judiciously using pesticides and other chemicals in a responsible manner.
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    Estimating environmental and human health benefits of reducing pesticide use through integrated pest management programs
    Mullen, Jeffrey D. (Virginia Tech, 1995)
    Estimates of the social benefits of integrated pest management (IPM) are fundamental to an informed assessment of the value of public expenditures for IPM research and extension. This study evaluates a subset of the potential social benefits if IPM adoption - reductions in the environmental and human health costs of pesticide use. A methodology is developed to estimate the environmental and human health costs of pesticide use associated with the production of any crop. The cost estimates for production under "conventional" (i.e. non-IPM) pest management are compared to the cost estimates associated with production under an IPM program to generate estimates of the environmental and human health benefits of IPM adoption. The development of the methodology resulted in: (1) a new algorithm for assigning levels of IPM adoption to agricultural producers; (2) the design and administration of a contingent valuation survey to estimate society's willingness to pay (WTP) to avoid pesticide related risks to the environment and human health; (3) a new technique for detecting payment vehicle bias in contingent valuation surveys; (4) a set of criteria for assigning to pesticidal active ingredients (a.i.) levels of relative risk that a. i. 's pose to eight environmental and human health categories; and (5) the assignment of relative risk levels to more than one hundred pesticidal active ingredients. All of these results are directly applicable to other studies of this kind. The analysis of Virginia apple production results in several recommendations regarding the design of future chemical use surveys conducted by United States Department of Agriculture. The analysis of the Early Leaf Spot Advisory system (ELSA) for Virginia peanut production estimates the environmental and human health benefits of ELSA to be approximately $840,000 per year.
  • Modeling long-run 'Striga' control in Mali
    Mullen, Jeffrey D.; Kebe, D.; Taylor, Daniel B.; Fofana, M. (1998)
    The model that is developed in this paper is capable of identifying effective, affordable Striga control practices, as well as potential barriers to the adoption of those practices. This is not only a valuable tool for guiding the design of new field trials to empirically test the effects of Striga control packages, but may also be used to identify policy options for facilitating their adoption.