Survey results reveal that 20 years of integrated pest management in Arizona cotton has significantly reduced insecticide use, saved farmers hundreds of millions of dollars, and kept huge amounts of chemical active ingredient out of the environment.

These staggering survey findings, along with others, are why, even during the Great Recession, the University of Arizona (UA) continues to effectively fund its integrated pest management (IPM) program.

While land grant universities nationwide slice away at agricultural research programs due to budget restraints, the UA expanded its IPM staff by five people last year.

“The IPM cluster hire is a phenomenal accomplishment at a time when Cooperative Extension funding around the country is shrinking,” said Al Fournier, associate director of the UA’s Pest Management Center (APMC) in Maricopa, Ariz. “We’ve been successful with IPM and continue to grow. Successful numbers gain the attention of UA administrators.”

Fournier discussed UA IPM successes in low desert agriculture during a mid-season cotton workshop in Yuma, Ariz. 

Arizona IPM success is based on effective numbers gathering over two decades through UA-conducted crop pest loss surveys for cotton. After each harvest, IPM staff holds grassroots meetings with pest control advisers, farmers, and industry representatives to gain season long crop-pest data.

The crop pest loss survey collects information about the intention behind the sprays, rather than strictly tallying pesticide use.

“Good data is powerful,” Fournier said. “These data provide insight on pest management problems and effective solutions.”

The grassroots feedback focuses on important criteria: the idealized yield versus actual yield for each crop, estimated yield losses from all factors, estimated yield losses by specific pests, insecticide application costs, scouting costs, pest infestations, and the number of acres treated.

The group is quizzed about the specific pest targets in control decisions. Yield loss can be attributed to weather, pests, irrigation, or other management limitations.

Each year, independent PCA Ben Hoyler of Bug Off LLC in Casa Grande, Ariz. participates in the cotton pest loss survey workshop. Hoyler advises on cotton grown in Pima and Pinal counties in central Arizona.

“The top causes for yield loss are the weather and insects in my area,” Hoyler said. “Lygus is the most common insect causing yield loss, but crop losses have declined in recent years. The insect bill has been lighter.”

In 2004, Ellsworth in collaboration with UA scientist John Palumbo expanded the crop pest loss program with separate surveys for head lettuce and melons (watermelon and cantaloupe) with funding assistance from the Western IPM Center. In addition to pest data, the APMC today collects information on weeds and diseases.

The origin of the UA crop pest loss surveys can be traced back to a National Cotton Council cotton insect loss survey initiated during the Beltwide Cotton Conferences in the late 1970s. Today, each cotton-producing state has a designated contact person responsible for coordinating survey data at the state level, which is submitted annually and published online by Mississippi State University. Peter Ellsworth, APMC Director, serves as the Arizona contact for the national survey.

The two decades of survey findings highlight notable changes in cotton pest management. Insecticide usage in Arizona cotton began dropping in 1996 with the introductions of insect growth regulators, Bt cotton, and the Arizona IPM plan.

Insecticide use dropped further with the launch of the pink bollworm (PBW) eradication program beginning in eastern and central Arizona in 2006 and the introduction of a lygus feeding inhibitor the same year.

“Arizona statewide cotton insecticide applications for all insects have dropped from an average of 9.0 sprays from 1990 to 1995 to an average of 1.5 sprays (annually) from 2006 through 2010,” Fournier told the crowd. “This is a cumulative savings to Arizona cotton growers of $220 million over 15 years.”

In addition, reduced pesticide use has kept 1.7 million pounds of active ingredient out of cotton fields per year since 2005. These facts clearly spell success for IPM in Arizona.