Study touts benefits of herbicides

After even a casual reading of the just-released National Center for Food and Agricultural Policy's study on herbicides, two things jump out.

First, thank God for the chemicals that beat back the ever-threatening, yield-sapping tide of weeds. Because of such chemicals there's food available to feed the world.

Second, according to the data compiled in the report, there's no going back to the good, old, pre-chemical days. No matter how many organic growers and consumers might wish otherwise, collective society has happily — perhaps blindly — jumped aboard the herbicide train and is now destined to ride it to the end of the line.

The study, a comprehensive look at the history, value and current usage of herbicides in this country, was begun by NCFAP some six months ago. It was commissioned by CropLife America, a trade organization that, says CLA president Jay Vroom, “represents the developers, manufacturers, formulators and distributors of plant science solutions for agriculture and pest management in the U.S. Our member companies produce, sell and distribute virtually all chemical crop protection and crop biotechnology products used by American farmers.”

Vroom and his CLA colleagues should be well-pleased with the report. It's a lobbyist's dream tool. Easy to understand and chock-full of impressive data, the study is surely destined for the hands and desks of important politicians looking for information to counter hyper-wary environmentalists.

The reason NCFAP undertook the report is that it's the first to go over “the value of herbicide technology for American growers,” says Leonard Gianessi, NCFAP senior research associate.

The study estimates the use of herbicides throughout the country. American growers, it turns out, annually use about 400 million pounds of herbicides on 200 million acres. Further, NCFAP estimates that growers spend nearly $7 billion for herbicides, application of herbicides and tech fees. All those pounds of chemicals are used to kill around 550 trillion weeds annually.

“We really wanted to answer some questions. What value do farmers get for herbicide expenditures? What value does society get from the use of these chemicals?” says Gianessi. In answering those questions, 40 crops in 48 states were studied.

What researchers found was that herbicides have made “substantial, important contributions to the productivity of U.S. agriculture,” says Gianessi. “There were substantial increases in yields from days prior to the use of herbicides and those after. We feel that this contribution needs to be acknowledged — these chemicals are taken for granted. American growers use herbicides routinely, and this study helps quantify some of the chemical's contributions.”

For example, Gianessi says should U.S. growers stop using herbicides and instead substitute up to 7 million workers, they'd still lose 20 percent of their production. That equates to 300 billion pounds of food and fiber lost — and remember: that's with 7 million more farm workers hand hoeing fields.

Herbicides are absolutely essential for maintenance of high yields in this country, argues Gianessi. If we truly wanted to maintain current yields and do away with herbicides, 70 million additional hoe-toting farmhands would be patrolling fields.

“That would mean one of every four U.S. citizens chopping weeds for a month every year,” says Gianessi. “There just isn't a future for a vast expansion of organic agriculture. Organic growers have gone back to hand-weeding and are spending hundreds of hours to grow a crop. Much of that labor is unpaid and yield losses still occur.”

Focusing on benefits to a specific crop, Darren Coppock, CEO of the National Association of Wheat Growers, says herbicides are incredibly important for wheat production. Coppock says there are four primary impacts we'd see if herbicides were removed from the production equation.

“Weeds compete with wheat plants for water and space,” says Coppock. “If weeds are out soaking up light and nutrients, then the wheat is going to suffer.

“If weeds aren't controlled, weed seed can spread to neighboring property.

“If we don't adequately control weeds, we can face severe quality discounts in the marketplace. Weeds like Canada thistle or jointed goat grass can lead to extensive discounting.

“Weeds that aren't adequately controlled can harbor plant diseases or vectors that spread disease.”

One thing herbicides do for wheat growers is allow greater flexibility in farming practices, says Coppock. Reduced tillage is one example. Tillage is effective in controlling weeds but can also lead to soil loss in wind or water erosion.

“Any time we pull a tillage implement across a field, the soil is dried down as far as the implement reaches. In a lot of wheat country, water is scarce anyway — especially in this six-year drought we're enduring in some areas — and conserving soil moisture is critical.”

Coppock says producers need a broad variety of tools available to address production problems. Having herbicides available is critical — “but we need more than one product or mode of action for a target weed. If two compounds are available, they can be rotated and the life and market of both compounds will be extended.”

And the cost can be justified, he says: the dollars growers spend on herbicides generate additional bushels. Those additional bushels often mean the difference between profit and loss overall.

“Producing the quantity and quality of wheat that feeds our nation and many others wouldn't be possible without these products. In fact, in this study, the impact just in wheat would be $982 million if herbicides were removed from the market and yield losses of 25 percent resulted,” says Coppock.

What if?

So what would the face of agriculture look like without herbicides? Would we still have farms encompassing thousands of acres?

“Many people have looked at this and believe more U.S. land would have to be brought into production,” says Gianessi. “Land that is currently in woods, parks and estuaries would have to be farmed.”

And here's where societal swings allowed herbicides to take root and hold fast. Gianessi says one of the reasons growers began using herbicides is a mass exodus of farm workers shortly after WWII. As those farmhands left, farmers had little choice but to employ herbicides in their place. As a result, yield losses weren't nearly at the levels they could have been.

What are the benefits of herbicides for Delta cotton farmers? Gianessi points to one of the study's charts referencing worker wage rates.

“For many years, wages were 10 cents per hour, so cotton farmers were able to get 30 hours of weed-pulling for $3 per acre,” he says. “One of the really dramatic changes in U.S. agriculture is the wage rate increase. Now, getting hoe labor — because of minimum wage, Social Security and transportation — a farmer is looking at around $9 per hour.

“In crops like rice, we saw yield increases of 50 percent to 70 percent across the board. Without herbicides, we wouldn't have that production. About half the rice we produce in this country is only possible because herbicides were introduced. You could argue that without herbicides, we wouldn't be growing 22 billion pounds of rice here but half that,” says Gianessi.

Another point repeatedly made by the men is that increasingly popular no-till production practices wouldn't be possible without herbicides. No-till is feasible only because growers can kill weeds before planting.

“If farmers give up no-tilling, there would be 300 billion pounds of soil erosion — erosion that isn't happening now because of herbicide use,” says Gianessi.

Sometimes things play out just right. In this vein, Vroom cites a story in the April 21 Los Angeles Times reporting that California labor unions want lawmakers to ban farm workers from pulling weeds by hand.

“They claim it causes back injuries and propose that more chemicals and special tools be employed. It may be serendipity that the timing of that story comes out the same week we unveil this study.”

(Editor's note: to see “The Value of Herbicides in U.S. Crop Production” study, go to

e-mail: [email protected].

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