Community Collaboration--Why Pest Resistance Management must Involve Group Action

April 8, 2020

By Paul Lasley, Iowa State University Sociologist

In my last editorial I argued that group action is required if we are to effectively manage field crop pests by concluding, “Some things are too big for anyone to accomplish alone and too important not to try to do together.”  

There is little doubt that productivity gains in corn and soybeans can be attributed, in part, to better pest management, which often relies upon herbicides and insecticides. However these pesticides are becoming less effective.

There is increasing evidence across the Midwestern and Southern states that weeds are rapidly developing resistance to existing herbicides.  In Iowa, marestail, giant ragweed, and waterhemp are showing resistance to glyphosate, commonly known as round-up, a staple in weed management.  Western corn root worms are developing Bt resistance, suggesting that evolution is giving root worms an upper hand.  Bt proteins that are lethal to root worms is a key component in managing this destructive corn insect pest.   Without Bt-based rootworm control, producers will likely need to use soil-applied insecticides combined with rotations to soybeans every three years or so.

What are the implications of weed and insect resistance?   Without effective herbicides, producers will likely find the only viable solution is the cultivator that “grandpa” used 40 years ago.  For those of us raised in the days where cultivators were the only option, it is mind-boggling to think about the additional hours and expenses of returning to mechanical cultivation.   In fields of heavy weed infestation, yield loss coupled with additional production expenses will contribute to increasing financial pressures on growers. Beyond the significant financial costs will be substantial increases in soil erosion if crop cultivation becomes more widespread.  

With increased Bt immunity among root worms, there may be little choice but to rotate crops more frequently or consider growing continuous corn with reduced yields and profits.  Again, critics who are quick to blame farmers might address the constraints of farmers rotating their crops.  The failure to consider the structural constraints and limited options in farming might reveal that the lack of choices rather than poor management is the culprit in explaining why Iowa is predominantly a corn-soybean state.  

At a recent demonstration field plot, a colleague commented that “if only farmers would follow our recommendations, pest resistance wouldn’t be a problem.“   I found his remark tactless on two fronts; first it is a classic “blame the victim response” that it is farmers’ fault if current pesticides are failing to control weeds and insects.  Secondly, his thinking appears to be shaped by an incrementalism approach that weed and insect resistance can be approached on case-by-case basis by working with individual farmers.  The expert model of science that seems to be guiding his thinking is limited to providing advice to producers, without considering the breakdown within the current pest management practices.  In spite of mounting evidence of weed and insect resistance across the farm belt, there is resistance among many to consider new approaches to pest management so we continue down the same paths that lead to resistance becoming an issue.

However there are others who are recognize the benefits of a community or network approach.  These innovative groups recognize that pest resistance management must involve group action.  This is not an academic discussion; a group of growers, chemical company representatives, crop advisors and extension staff in Harrison County, Iowa are demonstrating that a community response to pest resistant management is possible and necessary. 

The uniqueness of this grass-roots effort is reminiscent of earlier times when farmers and local community members understood the wisdom that “Some things are too big for anyone to accomplish alone and too important not to try to do together.”  

In my next column I will review what lessons have been learned thus far in the Harrison county experience and what key ingredients are necessary for group action to occur.