Since the mid-1990s, the Global Positioning System (GPS) constellation of 24 satellites orbiting 10,800 miles (17,500km) above Earth has caught the attention of farmers and urban dwellers worldwide. GPS technology delivers a range of benefits to growers. As global markets become more competitive and an increasingly populated world reduces available farm land, GPS guidance is now being relied upon to drive productivity and efficiencies in agriculture—from ground preparation to fertilizer application, planting, spraying and harvesting.
The round-about path of precision agriculture
Widespread commercial trials of GPS-based precision farming began in the mid-1900s. Initially, the focus was on site-specific techniques, where definite locations in the field were mapped for yield and then treated variably with farm inputs such as seed, fertilizer, lime and crop protection treatment. The initial aim of precision farming was to increase farm profitability by using variable rates of farm inputs to increase yield and lower input costs. But with complex biological systems, widely differing farm management practices and erratic weather—among many other variables—this goal was difficult to achieve. Although some growers could show measurable benefits, many others were unable to realize any such gains that could be detected by their agronomic systems and management style.
This lack of predictability greatly hindered the adoption of site-specific precision agriculture, which had made its debut in the late 1980s.
Agricultural Resource Management Survey (ARMS) data. For example, in the late 1990s, variable rate technology (VRT) was used to manage soil fertility—mainly N, P, K and lime—on nearly 18 percent of U.S. planted corn area. However, ARMS data indicate that this rate was less than 10 percent of corn planted in 2001, and even lower on soybeans.
As the definitive 2005 Purdue University study cited above notes: “Worldwide, the adoption of precision agriculture technology has been slower and more localized than many analysts in the 1990s expected. In addition, the study includes these relevant facts:
• Yield monitor adoption: In 2000, the U.S. had about 134 yield monitors per million acres (417,500 hectares) of grain or oilseed crops—or about one yield monitor per 7,500 acres (3,000 hectares). About 37 percent of these yield monitors were being used in conjunction with GPS.
• Precision agriculture usage: In 2001 (the latest year for which these types of ARMS data are available), the percentage of U.S. corn on which precision agriculture technologies were used included: Yield monitor – 36.5%, Yield map (yield monitor w/GPS) – 13.7%, Geo-referenced soil map – 25.0 %, Remotely-sensed (e.g. satellite) 3.4%.
• Pesticide VRT increasing: Variable rate technology for crop protection chemicals appears to be on the upswing, although overall adoption rates are still low (1–3 percent of acres treated), based on most-recent ARMS data.
• Nitrogen VRT promising: The most commercially viable on-the-go technologies for crop production at present focus largely on varying nitrogen fertilizer application rates within fields (as opposed to phosphorus or potash).
• Economic returns from GPS systems are being measured and proved: A separate 2002 study of GPS auto guidance concludes, in part, “ DGPS auto guidance will be profitable for a substantial group of Corn Belt farmers in the next few years. This will primarily be growers who are now farming as many acres as they can with a given set of equipment. The initial benefit for many growers will come from being able to expand farm size with the same equipment set. A $15,000 investment in DGPS auto guidance is a relatively inexpensive way to expand equipment capacity by several hundred acres.”
• Especially significant: Overall, the costs of information technology hardware and software are continually declining as the productivity of such technology is increasing.
Rapid Adoption of GPS Guidance and Automated Steering
In contrast to variable rate technology, between 1999 and 2006 extremely rapid GPS-driven technology adoption took hold as demand soared for GPS-based guidance and equipment automation (or automated steering) systems. Massive adoptionof various GPS systems to help guide and automatically steer farm machinery and implements—often to sub-inch levels—is becoming a technological and social phenomenon.
The rapid adoption of these GPS systems is being driven by various factors, including the following:
• Tangible payback that customers receive from their GPS-based guidance systems, including improved in-field productivity, reduced crop inputs such as fuel, fertilizer and chemicals, reduced operator fatigue, and the ability to operate machinery longer hours.
• Simple installation and operation.
• Lower cost of guidance technology—noted previously. As with most new technology, especially electronics, the cost of GPS systems continues to decrease.
Thousands of growers operating GPS guidance systems often report tangible benefits after the first few days of using their systems. As a result, more users are indicating interest in trying other aspects of precision agriculture. This phenomenon is generating a surge of interest in site-specific technologies such as yield monitoring and mapping, precision placement and rate control of crop inputs. Top managers and commercial applicators are also adopting data management systems that provide improved field record keeping with the aid of in-cab computers and data loggers. Such systems also fill a significant need for application mapping, accompanied by “proof of performance” data to meet increasingly stringent legal and environmental demands.
As a result, it now appears that the greatest opportunity to expand precision agriculture as originally conceived is to better inform and educate growers on the benefits of GPS-guidance systems.
Once growers can actually measure the value returned by their GPS guidance or automated steering systems—in gallons of fuel saved, hours of reduced labor, additional acres covered per day, or dollars of additional grain, cotton, potatoes or peanuts sold—they feel comfortable about using these systems to further reduce costs and increase income. In other words, the satisfaction and confidence gained from a GPS-based guidance system makes it relatively easy for many growers to upgrade hardware and/or software in order to achieve more automation of their farming operation—all from within the cab.
Interestingly, GPS-based guidance systems often elicit multi-sensory responses from those who purchase and/or operate them: Such systems not only make it possible for managers to see economic returns on their equipment investment, they also make many growers feel as if they are in better operational and economic control of their operation than ever before.
(Based on – http://www.gpsags.com/media/Precision-Farming-Whitepaper.pdf)