Yield Monitoring Technology for Irrigated Cotton and Grains in Arizona: Hardware and Software Selection

The development of commercial-grade yield monitoring technology in the US dates back to the early 1990’s when a new paradigm of “site-specific management” was introduced. By 1997, 14.6% of retail crop input dealers were engaged in sales and technical support for yield monitors (Whipker and Akridge, 2009). In 2011, this figure had grown to 35.6% (Whipker and Erickson, 2011). The use of yield monitors is particularly strong in the US-Midwest where large acreage of corn and soybeans are harvested with instrumented grain combines. In the Corn Belt (Illinois, Indiana, Iowa, Missouri, Ohio) yield monitor use grew from 28% of corn acreage in 2001 to 44% in 2005 (Agricultural Resource Management Survey, USDA, ERS/NASS). Prescription-based fertility management is one practical application driving this upward trend in the adoption of yield monitoring technology. For this use, yield monitors with GPS receivers enable collection of geographic data that are analyzed with GIS software to pinpoint yield variation within the field.

In the context of irrigated agriculture of the semi-desert, yield monitors have a place as a management tool to quantify the impact of management practices including water, fertility, plant growth (in cotton), pest control, variety selection, and others. The analysis of field-to-field variability in yield can also be used to improve financial decisions such as levels of crop insurance. Yield maps are a key step to understanding what the main drivers of variability are in a given field and can serve three main purposes: provide real-time yield quantities and other data for short term decision making such as scheduling of harvest operations and harvest equipment management, geo-reference yield data for mapping and spatial analysis for future management decisions, and as a basis to create prescription maps for site-specific chemical applications. There is a wealth of information that can be extracted from yield maps and there are many commercial technologies available to Arizona growers.

The main goal of this publication is to serve as a guide for growers and custom-harvest contractors to assist them in selecting the best option for yield monitoring technology for their operations. When it comes to yield monitoring technology for grains and cotton, growers and custom-harvest contractors have a wide variety of options to choose from. Selecting the right system requires careful consideration of technical specifications of existing equipment and/or options available in new equipment. This article provides information for a basic understanding of the principles of operation of these systems with the goal of providing a solid base to make good decisions in terms of hardware and software selection.