Excerpts from USDA Report on Precision Agriculture
Precision agriculture has not been widely adopted, to date. Because it is a suite of technologies that can be adopted piecemeal and combined in various ways, estimating the current level of adoption is difficult. Only a small percentage of farmers actively seek out new technologies and apply them.
Adoption of precision agriculture for subfield management is a refinement of good whole-field management practices. USDA's Cropping Practices Survey data for 1994 show that only a third of acres planted to major field crops (corn, wheat, soybeans, cotton, and potatoes) was soil-tested for nutrients. Pest scouting was done on slightly more than half of planted acres. Given the relatively low adoption of whole-field practices, the rapid adoption of subfield management technologies is not likely.
Precision agriculture is driven by computers, but a USDA survey shows that only 31 percent of the 2 million U.S. farmers and ranchers had computers in 1997, and only 13 percent had Internet access. A 1996 Purdue University survey of 1,500 ag chemical dealers found that only about a quarter of dealers had 10 percent or more of their customers using field mapping or other PA practices. A quarter of dealers surveyed expected that over 30 percent of their customers would be using field mapping, yield monitors, and other precision ag techniques within 2 years.
Combine-mounted crop yield monitors are one of the most popular ways for producers to get into precision agriculture, with industry sources reporting about 17,000 in use in North America in 1997, up from 50 in 1992. Commercially available yield monitors are currently available only for corn, soybeans, and wheat, and are being developed for bulky crops like potatoes, sugar beets, and peanuts.
Co-ops and other input dealers are key drivers in precision agriculture adoption. The Purdue University survey also found that by 1998, 30 percent of the respondents expected to offer grid soil sampling with GPS, 35 percent expected to offer field mapping, and 29 percent expected to offer controller-driven variable-rate application. There are important regional and size differences in expected dealer adoption of PA services: 45 percent of Midwest dealers and 54 percent of co-ops and large independent dealers expected to offer field mapping by 1998 versus 17 percent in other regions and 34 percent of small independent dealers.
There has been some concern that there is a scale bias to precision agriculture, with larger farms more able to adopt and reaping more potential gains. PA technologies can give operators of large farms the same explicit detailed knowledge of their land that operators of small farms have had implicitly. However, the size of the investment required for precision agriculture (about $7,000 for a yield monitor and GPS receiver, plus $3-$7 per acre for grid soil testing) is not prohibitive for smaller operations.
The most expensive component of precision agriculture, variable-rate fertilizer application, is offered on a custom basis by fertilizer dealers, with the cost often embedded in fertilizer material prices. Although many larger farms have been PA innovators, the advantage may be one of technological sophistication rather than deep capital resources.
Implications for Profits & for the Environment
At this stage in the emergence of precision agriculture, neither the economic nor environmental advantages of subfield management have been definitively demonstrated. Any assessment of precision agriculture has several serious conceptual problems to overcome. Information technologies often contribute in indirect ways to the farmer's better understanding of his cropping system and changes to it. Some of those changes, such as reductions in total use of chemical fertilizers, are easily observed. Other changes are more subtle but will be expressed in higher productivity and lower runoff that, given the year-to-year variation in results due to a multitude of factors, may be impossible to isolate.
Because precision agriculture is a suite of technological tools that can be adopted piecemeal or in varying combinations, there are unlikely to be uniform answers regarding performance for all the possible permutations. Precision agriculture adjusts management decisions to suit variations in resource conditions. Because these conditions vary so widely from farm to farm and region to region, generalizations about performance across all situations are unlikely to be true.
Current costs for precision agriculture are estimated at $9-$23 per acre; future costs are likely to drop. Much less is known about the labor and time needed to integrate the systems and keep them running, or what true custom rates would be if "unbundled" from services provided by farm chemical and input dealers. Most of the costs likely to be borne by the farmer are to acquire information about the soils, yields, and pest problems occurring over the field. Chemical dealers are making major investments in PA equipment, particularly VRT applicators, because they can purchase larger, more economical equipment and can spread the costs over many farmers' fields, reducing the cost per acre.
Most of the scant literature on the profitability of precision agriculture focuses on variable-rate fertilizer application. A review of 15 studies showed that precision methods were not profitable in 5 studies, profitable in 5, and showed mixed results in 3 (2 studies were inconclusive).
The studies showed little uniformity in the period over which investments were amortized, the discount rate, which PA components farmers invest in and which are acquired through consultants or dealers at custom rates, the grid size for soil sampling, and the nutrients that are managed on a precision basis. The duration of studies varied as well, with empirical studies at most 3 years, and simulation studies varying from 1 to 24 years. There is likely as much temporal variation in PA profitability as there is across resource situations, so the longer the study, the more reliable the results.
Cost reduction is only part of the promise of precision agriculture. Analysis by USDA's Economic Research Service shows that a 10-percent reduction in nutrient and pesticide applications for major field crops would reduce costs only $2.14 to $23.97 per acre, while a 10-percent increase in yields would produce gains of $11 to $162 per acre. Thus, any increases in crop yields from precision management are likely to be as much or more of a basis for adoption than are cost reductions.
Much of the enthusiasm off the farm for precision agriculture can be attributed to the eminent good sense of matching input applications to plant needs. Precision agriculture is simply a more disaggregated version of the kinds of best management practices (BMP's) already recommended at the field level. But there is much more to learn about the impact of PA on water and air quality relative to conventional techniques.
Plot studies in Minnesota and Missouri showed reductions in nitrogen applied and in unrecovered nitrogen in the soil with variable-rate application, at little or no loss in crop yield. A study in Nebraska demonstrated reductions in pesticide applications from early detection, and reductions in herbicides from selective application to weeds.
Synergy between variable-rate application and biotechnology offers another way that precision can improve agriculture's environmental performance. Seed systems enhanced with natural insecticidal properties of Bacillus thuringiensis (Bt) can confer economic and environmental benefits when employed on a whole-field basis, but are likely to be more effective when applied on a precision basis.
For example, if there are yield penalties associated with some of these varieties, they may be planted only in areas of high weed infestation or where onboard sensors indicate higher organic matter (that could be associated with greater need for pre-emergence herbicide application). Precision application of Bt-enhanced seed could slow the development of resistance compared with whole-field application.
Public Roles in Precision Agriculture
One of the more important charges to the National Research Council committee studying precision agriculture was to assess appropriate public roles in the development of the technology. Each of the recommendations made by the committee implicitly envisions a role for public agencies.
Precision agriculture is based on satellite imagery, the GPS satellite network, and the Internet, all developed with massive public investments for defense and space objectives. Despite this initial large, but inadvertent, public role in technological infrastructure investments, the committee was generally convinced that private interests were well able and motivated to further the development and dissemination of precision agriculture. The committee regarded public roles in measurement technology, new approaches to research, unbiased evaluation, and training and education as filling critical ancillary or facilitative roles in an otherwise robust private development of the technologies.
Publicly funded research into the science underlying potential improvements in measurement methods is key, both in developing new sensors and manipulating and analyzing spatially referenced data. The committee also called for new approaches to basic agronomic research. PA methods for the first time open up the possibility of accounting for interactions between factors affecting crop growth in a way that cuts across scientific disciplines, using data generated by precision farmers themselves. The ever finer spatial scales enabled by the technology make earlier generalizations from limited plot studies obsolete.
An area of concern for the committee is an objective evaluation of the pros and cons of PA technologies. Farmers are caught in a barrage of competing claims and hyperbole generated by developers and boosters of precision agriculture. Unbiased evaluations of the economic and environmental performance of precision cropping systems are needed to help farmers decide whether and when to adopt these new methods. The committee concluded that public leadership in collaborations among agencies, professional organizations, technology providers, and producers would provide the fullest and fairest basis for comparing methods.
The committee's other recommendations concern the movement, ownership, aggregation, and provision of data. In general, the capacity to move large quantities of digital data has been developed in proportion to population, with the highest "band width" for electronic data in urban areas. Widespread adoption of precision agriculture will be accompanied by a many-fold expansion in the volume of electronic data moving among producers, suppliers, consultants, and customers in rural areas. Ensuring that adequate connectivity exists in rural areas is at least partly a public role.
The large volume of data generated by grid soil testing, satellite images, crop yield monitoring, and other precision technologies has to be shared among producers (who may or may not collect the data), consultants and input suppliers, Extension agents, university and USDA researchers, and commodity buyers. All of these may exercise some control or ownership over the data. |
