A Faster Way To Clean Roots

Agronomists, plant pathologists, and botanists—to name a few—are interested in the effects of soil and crop management practices on crop root systems. But before they can begin their studies, scientists usually have to spend time and energy cleaning soil off the roots. A new invention by the Agricultural Research Service (ARS) may help with that.

Soil scientist Joseph G. Benjamin, of ARS's Central Great Plains Research Station in Akron, Colorado, has created a root washer with a rotary design to automate and speed up the process. Other devices require more attention from the operator. The new device can clean up to 24 samples at a time, more than previous washers.

The washing cycle starts when a technician places a sample of soil and roots in the machine's chambers. As the sample rotates within the machine, it is dipped into and sprayed with water to remove the soil. Mud exits from the back of the machine. The cycle takes about 90 minutes, and the roots, which are not damaged by the machine, are then ready for study.

"The root washer works well to easily and quickly separate plant roots and other organic materials from the soil," Benjamin says. He also points out that his device can wash larger samples than other washers can.

Once the roots are clean, a flatbed scanner is then used to digitize images of them for scientists to analyze with computer software. Through mathematical equations, Benjamin is able to determine the surface area of the roots contained in the sample. As Benjamin points out, "The human eye is still the best discriminator at determining what materials are roots and what are not."

Benjamin's root washer is an enlarged version of a weed-seed washer invented by weed scientist Lori J. Wiles and others in ARS's Water Management Research Unit, at Fort Collins, Colorado. Before her invention, there was nothing available commercially to quickly wash soil from seeds.—By David Elstein, Agricultural Research Service Information Staff.

Joseph G. Benjamin is with the USDA-ARS Central Great Plains Research Station, 40335 Country Road GG, Akron, CO 80720; phone (970) 345-0518, fax (970) 345-2088.

"A Faster Way To Clean Roots" was published in the January 2004 issue of Agricultural Research magazine.