Scientists of the Corn

By Susanna Pearlstein

Wandering through a corn field, you might find stillness, quiet, order, perhaps a tassel-lined sky. At our corn field at the Oregon State University Vegetable Research Farm, you will find a hydraulic drill and a team of EPA staff from Oklahoma’s Ground Water and Ecosystems Restoration Division.  The crew brought two hydraulic drills in a semi-truck to Corvallis, Oregon, to bring to life a study that had taken a year to plan.

an aerial view of a corn field with two paths for research

Aerial view of the completed field installs. Photo by Keith Sawicz

I met them at the corn field, armed with pastries and the excitement of knowing that all the planning, site searching, relationship building, corn planting, and a host of other activities had been successful. The results of the study will help us understand how nitrate moves into groundwater.


A team of researchers installing the sensor ray in the corn field

The team installing a sensor array. Photo: Steve Hutchins

Farmers apply nitrogen to crops like corn to help them grow and supplement the nutrients that they take out of the soil. It is essential to monitor water quality related to farming practices because any extra nitrogen that is not used by the plant may move down through the soil as nitrate. Nitrate is found in some local drinking water supplies, and it can be particularly harmful to infants.


The study will help explain how we can protect drinking water by planting crops between corn rows to keep the nitrogen in the field. The crop is left behind after corn harvest as a cover crop rather than leaving the fields bare. Scientists advocate interplanting cover crops to help keep nitrate from leaching into groundwater and surface waters across the U.S

EPA researchers stand proudly beside a sensor in a field of corn.

Steve and Susanna enthusiastically display the inner workings of the sensor dataloggers. Photo by Bart Faulkner.

Preparing the site meant that the crew from EPA spent the first part of September patiently guiding the drills through the soil to several depths within the vadose zone, the space between the soil surface and the top of the groundwater. Under the expert eye of the licensed driller James “JR” Cantrall of Northern Lights Drilling, the drill team installed these devices and drilled groundwater wells. In addition to the groundwater wells, which sample below the vadose zone in the actual groundwater, scientists installed lysimeters, soil moisture probes, and tensiometers within the vadose zone. Lysimeters are porous cups that allow water samples to be taken under vacuum as the water infiltrates through the soil. Soil moisture probes will monitor how much moisture is in the soil, and tensiometer sensors will show the soil’s capacity to take up additional moisture. All together, these devices allow for critical evaluation of changes in water quality as it moves through the soil and into groundwater.

With the site up and running now EPA will monitor the soil and groundwater biweekly for the next four years as part of EPA’s Safe and Sustainable Water Resources research program. Please visit our corn field, either in person or by watching for our updates and publications. We’re looking forward to sharing the story these data will tell!

About the Author: Susanna Pearlstein is an Oak Ridge Institute for Science and Education (ORISE) Postdoctoral Researcher based at the U.S. EPA in Corvallis, OR. She works with Jana Compton and co-leads the Partnership to Improve Nutrient Efficiency, a multi-stakeholder effort in the southern Willamette Valley.

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