The science and practice of crop protection are seeing revolutionary change in the second decade of the 21st century. The change is driven by farmers’ need to operate profitably despite often challenging circumstances, and by consumer demands that product quality not only be top flight but that products be grown “responsibly,” with an eye to the environmental, social, regulatory and economic impacts implicit in the growing of foodstuffs and other agricultural offerings.

Today, Integrated Pest Management (IPM), seen by some only a decade or two ago as experimental and a risky strategy to implement, has become a standard for crop protection for many, if not most, growers. Now, researchers are working to expand the knowledge necessary to the next step in the future of crop protection with an approach one U.S. Department of Agriculture-supported entity, the Sustainable Agriculture Research and Education (SARE) program terms a “whole-farm” or “wield many little hammers” strategy. This approach to pest control is based on “recognizing the importance of many tactics rather than just one deceptively easy fix” to control insects, weeds and diseases.

The whole-farm strategy is based on research demonstrating growers utilizing the whole arsenal of approaches to pest control, especially biological controls, in devising their crop protection approaches are able to optimize their ability to best achieve the delicate balance between profitability, product quality, product quantity and all other inputs and outputs that, as a whole, determine the level of success a grower might seek.

The beneficial impacts of the little hammers approach to pest control, according to SARE’s publication “A Whole Farm Approach To Managing Pests,” come because crop protection game plans are strengthened when various individual strategies are used together; the risk of crop failure is lessened because the burden of crop protection is distributed, the rate at which pests adapt/evolve resistance to a given pest management tactic is reduced, potential environmental impacts (excess runoff, reductions in the populations of beneficial predators, etc.) are minimized, operating costs are reduced, and profitability is enhanced by minimizing the need for purchased inputs.

Increased attention to biological and cultural controls as mainstays for crop protection with chemical and other inputs in a backup role is not really as revolutionary as it might seem to be to some. According to one entomologist, “We’re seeing a growing body of interest in biological controls today; but the basic approaches are hundreds of years old. We’re just learning a lot more about subtle tweaks to simple strategies that can help us reduce the need to rely too heavily on some inputs.”

Perimeter trap cropping is an example of the kinds of “subtle tweaks to simple strategies” researchers noted. Work published by University of Connecticut Extension specialists in 2002 with review undertaken in 2012 examined the positive effects the technique can achieve including, for farmers, improved profitability, improved yield and improved quality.

Crimson clover planted as a cover crop attracts pollinators and other beneficial insects, fixes nitrogen in the soil, and helps prevent erosion.

Insects go for the gusto

Insects are no different than people in some ways, particularly when it comes to appetite. Offer a pest something delicious to eat in place of something that’s just OK, and the bug will go for delicious. A trap crop is a plant species, variety or “…a different growth stage of the same species of the main crop” that is more attractive to a pest than the main crop is.

According researchers at the University of Connecticut’s IPM study “Perimeter Trap Cropping Works,” perimeter trap cropping (PTC) “involves planting the attractive plant species so that it completely encircles the main crop, like fortress walls.

“PTC functions by concentrating and or killing the pest in the border area, while reducing pest numbers and disease spread on the unsprayed cash crop in the center and by preserving natural enemies. The effectiveness of this trap crop technique can often be improved by adding other perimeter defenses like biological, mechanical, cultural or chemical control tactics (that is, border sprays), or with pest attractants and repellants.

“The perimeter orientation of the trap crop and defenses improves efficacy because the barrier intercepts the pest migration regardless of the direction of attack, rather than trying to get the pest to move to where you want it to go. The technique may not always eliminate the pest completely, but it can substantially reduce their populations on the main crop. In recent years, PTC has dramatically increased the efficacy of trap cropping on a variety of crops.”

Demonstrating the effectiveness of PTC’s researchers reported in its study, “researchers in Florida were able to keep the diamondback moth from reaching action thresholds in nine commercial cabbage fields by surrounding them with two rows of collards. Sixty percent of the nearby control fields without collards exceeded thresholds. Insecticide use was reduced by 56 percent.”

In Connecticut itself, the study stated, “bell peppers surrounded by the trap crop produced at least 98 percent pest-free fruit at harvest, compared with all-bell plots, which had 15 percent of the fruit infested. Commercial farmers using PTC harvested 99.99 percent clean fruit, experienced the best pest control in the history of the farms and had better pest control than farms that had used well-timed, full-field sprays. They reduced their insecticide use on peppers by up to 89 percent.”

Trap cropping is just one of the “many little hammers,” being investigated by researchers concerned with expanding the natural or biological controls for controlling crop pests. The modern grower has thousands of options to choose from, many of which are nearly cost free.

In broad brush strokes, the various little hammers available to the grower include cultural, biological and mechanical controls; chemical approaches; physical barriers and more.

Growing rye between vineyard rows in Monterey County, California helps suppress weeds by producing a substance that inhibits weed germination and, attracts beneficial insects like lady bugs.

Hundreds of little hammers

The modern grower has hundreds of choices regarding implementing a crop protection game plan. The best choices are determined by the nature of the crop to be protected, the soil, landscape and weather conditions prevalent in an area, and the nature of the predators likely to attack the crop at various times in the growth cycle.

No two fields are alike and not all crop control approaches are appropriate to every crop. Perimeter trap cropping, for example, has limited effectiveness if insects are flying or drifting in from the air but, for every predator there is a defense; the key to successful crop protection is finding the best mix of “little hammers” for the individual crop and even the individual field.

Fortunately, nearly every grower has easy access to cutting edge research on crop protection through the extension programs established by land grant colleges and universities, data and information available through the USDA and the research organizations like SARE funded by USDA, and the internet puts all that information only key strokes away. Hundreds of articles on nearly any aspect of crop control are available. In today’s economic climate, the grower making best use of those information sources has a leg up on the competition.

Cotton growing with a cover crop mix of rye and crimson clover. The clover adds nitrogen to the soil while the rye attracts beneficial insects.

Customer’s always right

In nearly every economic sector imaginable, customers’ preferences and profitability are inextricably linked; the field of agriculture is no exception. Consumers today are demonstrating ever-growing interest in how food is grown.

Foods grown using ecological principles are in high demand, and that demand is being demonstrated by companies like NORPAC Foods in Oregon, a 200-plus growers’ cooperative. The cooperative processes 600 million pounds of food grown on its member’s 40,000 acres of Willamette Valley farms each year.

NORPAC requires its member farms to sign on to an independently audited nine-point program for sustainability that includes addressing recycling, water use and reuse, habitat conservation and other approaches to crop control and sustainable agriculture.

In 2017, the many-little-hammers approach is not only being widely adopted, but it is also becoming an economic necessity for farmers seeking to responsibly improve bottom lines.