In the fourth part of Deciding Iowa’s six-part series on water, Dr. Shawn Ellerbroek and Dr. Emily Boevers turn their attention to the backbone of Iowa agriculture: row crops. Joined by Dr. Matt Helmers, they explore the challenges of an “annual cropping system” that leaks nutrients into our waterways, even when best practices are followed.

The conversation digs into:

• Why corn and soybeans dominate Iowa’s 24 million acres of row crops—and what that means for nitrate runoff.
• The limits of nitrogen management and why even “no-fertilizer” plots still lose nitrates.
• How cover crops and perennial systems mimic natural prairie and reduce leaching.
• The promise—and economic hurdles—of introducing small grains and forage crops into Iowa rotations.
• Why voluntary adoption alone may not be enough to protect our water.

This episode shines a light on the structural and economic obstacles of diversifying Iowa’s crop system, and what it will take for clean water solutions to take root.