The No-Till Trade-off

Researchers have been looking at why the water in western Lake Erie has been so gross with algae this year. Boats motored through fluorescent green slime over the summer and many of the beaches were under swimming advisories because of paint-like slicks along the shoreline. Some scientists say the biggest culprit feeding the algae is fertilizer washing off from farms. The Allegheny Front's Julie Grant reports that long time efforts to prevent farm pollution back may be inadvertently contributing to the problem.

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GRANT: Bob Sprunger is a fourth-generation dairy farmer in Dalton, Ohio. He grows alfalfa and corn on his 500 acres to feed his cows. And in recent years he's been trying something new: it's called no-till farming.

[SOUND: WALKING.]

This field had hay on it this summer. After they cut the hay, Sprunger would usually plow the leftover stalks, turning them under the soil. But this year, Sprunger just left the hay residue on the field and planted the corn right into it:

SPRUNGER: THIS IS A NO-TILL CORN FIELD. NOTHING WAS DISTURBED HERE BESIDES A SLIT TO PLANT THE SEED IN THE ROW.

GRANT: It looks kind of messy - the field is not nicely plowed. But it takes less energy from Sprunger: he doesn't have to till the soil. And some farm experts say that by planting seeds right into the remnants of previous crops, farmers create a protective armor on the soil surface. Mark Scarpitti says no-till farming prevents soil sediment from eroding and carrying fertilizers with it into the waterways.

Scarpitti is the state agronomist for Ohio. He remembers the pollution in Lake Erie back in the 1980s. Since then, he says no-till farming has gained popularity, and it's made a difference in reducing nutrients like phosphorous in the water:

SCARPITTI: WE HAVE DRAMATICALLY REDUCED THE AMOUNT OF SEDIMENT GETTING INTO OUR LAKES AND STREAMS, AND ALSO THEN THE NUTRIENTS THAT ARE ATTACHED TO THOSE SOIL PARTICLES.

GRANT: But even as the amount of phosphorous and other nutrients attached to eroding soil has been reduced, Lake Erie has still seen a new rise in toxic algae. And that algae grows by feeding on phosphorous.

Researcher David Baker has been studying this issue for 40-years at Heidelberg University.

With no-till farming, he says, phosphorous-based fertilizer is applied to the surface, but it isn't worked down into the soil. So it remains near the top. When it rains, Baker says the phosphorous can dissolve and run off the land into the waterways.

BAKER: AND SURE ENOUGH OUR MONITORING PROGRAMS SHOW THAT IT HAS INCREASED IN RATHER LARGE AMOUNTS. AND SO AT THIS POINT IN TIME, IN SPITE OF HAVING RATHER LARGE POLLUTION ABATEMENT PROGRAMS, WHAT WE SEE IS THAT WE HAVE MORE BIOAVAILABLE PHOSPHOROUS GOING INTO THE LAKE NOW THAN EVER BEFORE.

GRANT: Baker agrees that the continuing rise of no-till farming has reduced some forms of phosphorous from getting in Lake Erie: there is less phosphorous attached to soil sediment in the water. But he says no-till is contributing to the rise of dissolved phosphorous:

BAKER: LIKE MANY THINGS, THERE'S A CERTAIN TRADEOFF. AND THAT TRADEOFF SEEMS TO BE AN INCREASE IN DISSOLVED PHOSPHOROUS.

GRANT: And he says dissolved phosphorous is more conducive to algae growth--which seems to be why boaters and swimmers had so much algae to complain about this summer in western Lake Erie.

But agronomist Mark Scarpitti says there's more to the story. He says it's not the practice of no-til that leads to more dissolved phosphorous in the water--he says it's the large scale broadcast of fertilizers. Instead of putting fertilizer directly on the spot where a seed is planted, Scarpitti says many farmers today spray the entire field. He says most farmland today gets a lot more phosphorous than 20 or 30 years ago:

SCARPITTI: I THINK IT'S A RESULT OF PRODUCERS HAVING OVER THE YEARS TAKEN ON MORE LAND, THE FARMING OPERATIONS HAVE GOTTEN BIGGER. BUT I DON'T THINK IT WOULD BE ACCURATE TO SAY THAT NO-TILL DIRECTLY IS THE CAUSE.

GRANT: Scarpitti says instead of blaming no-till - researchers and farmers should look at the way the huge new farms are managing their chemicals.
He says farmers need to be educated on how to prevent farm nutrients from running off their fields into the waterways.

[SOUND: Sprunger farm.]

Back at the dairy farm, owner Bob Sprunger says farmers want that too. They pay a lot for fertilizers, and want to keep them on the fields.

For The Allegheny Front, I'm Julie Grant.