Economic and Environmental Impact Assessment of Tractor Guidance Technology

Abstract

E nergy consumption in agricultural systems has increased steadily over the past decades and accounts for approximately 17% of total energy consumption in the United States (Bora et al., 2012). Tractor guidance (TG) is a precision agriculture technology that allows for more spatially precise application of seed, fertilizer, and agro-chemicals when compared to ield operations conducted without GPS guidance. Using TG therefore simultaneously reduces environmental impacts associated with ineicient agricultural input usage (Brown et al., guidance and autosteering systems are widely used to increase operational eiciency, resulting in more even land coverage per unit of time. Producer adoption of best management practices is complex and, thereby, decision-support tools that help quantify costs and ben-eits may assist in technology transfer. Precision agriculture technology adoption requires capital and time investment. Until the 2000s, the adoption rate of precision agriculture was only 22% across the United States for major crops (Schimmelpfennig, 2016). To date, adoption of TG adoption is greater than use of variable rate application equipment. Further, based on a 2010 USDA Agricultural Resource Management Survey, only 29% of corn (Zea mays L.) producers adopted TG systems (Schimmelpfennig and Ebel, 2016), while 48% of producers adopted yield monitoring technologies. Projected eiciency gains for a farm operation are a function of (i) enhanced equipment eiciency as a result of greater efective ield coverage per hour (Shockley et al., 2011) and thereby lesser fuel, repair, maintenance, and labor cost per hectare; (ii) more spatially precise input application, leading to less overlap or gaps; and (iii) attendant yield gains as a function of more precise application. hese eiciency gains may appear straightforward but are dii-cult to quantify. For example, yield gains are only observable once annually, Abstract: Tractor guidance technology allows for more spatially precise input applications, which leads to eiciency gains that are diicult to quantify at the systems level. A decision-support tool, Tractor Guidance Analysis (TGA), was developed to quantify carbon equivalent (CE) emission reductions associated with this technology for three scenarios (500 ha each): (i) cotton (Gossypium hirsutum L.), (ii) soybean [Glycine max (L.) Merr.], and (iii) cotton and soybean mixed. Carbon equivalent emission reductions for cotton, soybean, and mixed enterprises were 27.5, 5.6, and 16.5 kg ha-1 , with attendant increases in farm proitability ($68,700, $16,900, and, $42,900, respectively). Tractor guidance led to total farm CE emission reductions of 15.7, 3.5, and 9.6 Mg for cotton, soybean, and mixed operations, respectively. These results highlight that CE reductions are (i) crop speciic, (ii) scale dependent, and (iii) equipment and input-use speciic. Consequently, TGA can improve agricultural sustainability by informing users of economic and environmental repercussions of tractor guidance and may thereby enhance technology adoption. Mention of trade names, proprietary products, or speciic equipment does not constitute a guarantee or warranty by the USDA and does not imply its approval to the exclusion of other products that may be suitable. Core Ideas • Tractor guidance (TG) technology allows for spatially precise input applications. • A decision-support tool was developed to quantify environmental and economic impacts of TG. • Greatest C equivalent emission reductions and cost savings occurred with Cotton-Only scenario. • TG was proitable for operations evaluated and led to C equivalent emissions reductions. • This tool may improve agricultural sustainability and enhance technology adoption.