Sometimes the best defense is a good offense. And using the tools and technology of precision agriculture makes a winning offense for production agriculture – higher yields, efficient use of inputs and smarter decisions.

And, if you run this offense well, it makes for great defense as well.

Last week at InfoAg, I moderated a session “Precision Phosphorus Application for The Lake Erie Watershed,” featuring Tom Bruulsema, Ph.D., northeast director of the International Plant Nutrition Institute (IPNI). Three days later, I was clearly reminded how relevant his work is as they turned off the water in Toledo, Ohio, due to contamination caused by algae in Lake Erie.

Nearly 500,000 Toledo-area residents were without water through the first weekend in August, according to the Cleveland Plain Dealer. The headline, “Todelo-area tap water contaminated” was at the top of the front page of its Sunday edition. The story was carried nationally with fertilizer and “industrial agriculture” prominent among the culprits. See the New York Times online story by clicking here.

Algae produces a toxin called microcystin when it dies off, and in this case, a bloom close to the city water intake resulted in levels of the toxin being pulled into the treatment plant where sampling showed levels too high for safe consumption. Algae blooms in Lake Erie have been getting worse in recent years and dissolved phosphorus (P) in the streams and rivers running into Lake Erie is seen as a principle cause, whether from fertilizer, manure or municipal waste.  Since about 75 percent of the basin is in cropland, crop producers can count on added public scrutiny in the years to come.

While the Lake Erie Basin and its nutrient management challenges may be far from home for you,”your dog is still in this fight” as they say. You can be sure that the folks in water treatment plants all across the country have read the news from Toledo and are wondering what they need to do to keep their citizens safe from any potential hazards caused from soil runoff. 

Research conducted in recent years by Bruulsema and others provides greater clarity for best practices to avoid excessive runoff of P. The 4Rs – right source, right rate, right time and right place – are key and the increased accuracy of precision agriculture brings answers in the placement category.

“Comparing strict long-term no-till to annual moldboard plowing, soil test P levels in the top two inches of soil can be three times higher than in the four to eight inch depth,” he explained. This stratification of phosphorus at the top of the soil profile makes for more runoff when storms come and surface P is carried away. That means broadcast application, while expedient, may not be the way to go.

“The right place to put P is close to the roots of the plant that need it,” said Bruulsema. “Corn especially needs P early in the growing season. Near the seed is a good place for it.” 

Handled well, this sort of placement can be the kind of good offense that means good defense. GPS-driven zone tillage equipment offers this sort of placement that is at the other end of the spectrum from fall-applied broadcast of fertilizer or manure on frozen or snow-covered ground, something Bruulsema said is “never the right time no matter what the source.” To gain a better understanding of what’s involved in managing P, click here.

As you apply the tools of precision agriculture to push toward those higher yields, being diligent toward optimizing inputs: right source, rate, time and place – will provide our industry with the defense against environmental issues and inappropriate regulations.