Jess Lowenberg-DeBoer

A Spatial Econometric Approach to the Economics of Site-Specific Nitrogen Management in Corn Production

The objective of this study is to determine the potential for using spatial econometric analysis of combine yield monitor data to estimate the site-specific crop response functions. The specific case study is for site-specific nitrogen (N) application to corn production in Argentina. Spatial structure of the yield data is modeled with landscape variables, spatially autoregressive error and groupwise heteroskedasticity. Results suggest that N response differs by landscape position, and that site-specific application may be modestly profitable. Profitability depends on the model specification used, with all spatial models consistently indicating profitability, whereas the nonspatial models do not.

Adding value to spatially managed inputs by understanding site-specific yield response

Many mechanized crop producers and agribusinesses are fascinated with precision agriculture technology, but adoption has lagged behind the expectations. Among the reasons for slow adoption of precision agriculture technology is that initial users focused excessively on in-field benefits from variable-rate fertilizer application using regional average fertilizer recommendations. This article illustrates how greater use of site-specific crop response information can improve variable rate input application recommendations. Precision agriculture is spatial information technology applied to agriculture. The technologies include global position systems (GPS), geographic information systems (GIS), yield monitoring sensors, and computer controlled within-field variable rate application (VRA) equipment. Experimentation with these technologies is occurring everywhere there is large scale mechanized agriculture. Commercial use has been greatest in the US, where 43% of farm retailers offered VRA services in 2001. Except for certain high-value crops like sugar beet, farmer adoption ofVRA has been modest. The farm level profitability of VRA continues to be questionable for bulk commodity crops. The theoretical model and illustration presented here suggest that VRA fertilization has not yet reached its profitability potential. Most VRA field trials to date have relied upon existing state-wide or regional input rate recommendations. Unobserved soil characteristics can potentially interact with an input to make its effect on yield vary site-specifically within fields. Failure to use site-specific response functions for VRA applications may lead to a misallocation of inputs just as great as that which results from using uniform applications instead of VRA. Agricultural economists have a long history of estimating output response to input applications. Several have started to develop tools to estimate site-specific responses from yield monitor and other precision agriculture data. Likewise, agricultural economists have developed an important body of research results on information value based on managing variabilitytypically in temporal settings. With these tools, a major potential exists to develop further benefits from precision agriculture technologies that permit truly spatially tailored input applications.

Forecasting long-term global fertilizer demand

Fertilizer demand forecasts are key to the success of long term plans for global food security and the profitability of the fertilizer industry. The study forecasts fertilizer demand in relation to soil nutrient status in nine regions. Asia is expected to account for about 40% of the global forecast of 187.7 million Mt in 2015 and 223.1 million Mt in 2030. Sub-Saharan Africa, where soil nutrient depletion is prevalent, will remain the region with the lowest consumption, about 1.1% of global consumption. Soil nutrient drawdown in regions with inadequate fertilizer use indicates soil nutrient depletion, which will in the long run exacerbate food shortages and undermine biofuels production plans. Food and fertilizer policy, farmer education, research and technology development, and other actions will be required to counter soil nutrient depletion.

An economic evaluation of horticultural alfalfa as a substitute for sphagnum peat moss.

Imported sphagnum peat holds a significant share of the US market for horticultural growing media, but the price of the product is relatively high due to transportation costs. Low-quality alfalfa may provide an effective substitute. The purpose of this research is to identify the characteristics consumers want in a horticultural organic material, to determine the cost competitiveness of an alfalfa-based substitute, and to determine the products market potential. Results suggest that most consumers would accept alfalfa as a substitute. Production cost estimates range from

Value of More Uniform Nitrogen Application Across the Toolbar

111.10 to

Evaluating the profitability of site-specific farming

162.71 per short ton, depending on the quality of the raw material used. Due to lower transportation costs, the wholesale and retail prices of this new product are estimated to be about 30% lower than sphagnum peat.

Economic Analysis of Row Spacing for Corn and Soybean

Variability of nitrogen (N) application rates with conventional anhydrous ammonia equipment is quite high. Technology is on the market to reduce variability of anhydrous ammonia application across the toolbar. A series of analyses were conducted to test the consequences of anhydrous ammonia application variability on both corn yields and the economics of investing in equipment to reduce that variability. In individual years and for specific locations, greater N application uniformity can have a yield advantage and/or promote more efficient use of N. Over several crop seasons, the yield gains to greater N uniformity may be less than 1 bu/acre. At current prices economic analysis indicates that this modest yield gain may justify an investment in equipment which would reduce the application rate variability by about half. However, more expensive equipment which provides an almost uniform application rate is not justifiable on benefits of N uniformity alone.