Perforated tile are buried under cropland to remove excess water detrimental to crop production. Farmers and landowners considering installing strips of prairie plants in their fields have asked about the possibility of roots growing into tile lines. To address this potential, Tim Younquist and Matt Helmers used video cameras to evaluate root penetration into the tile lines under prairie and continuous corn.
This news release and video summarize their results. Prairie and continuous corn showed similar levels of root growth and structure. The largest roots encountered were cottonwood tree saplings, which was growing in the prairie. Farmers or farmland owners implementing prairie strips will recognize the importance of managing such woody encroachment to avoid their roots encroaching into tile.
Sometimes farmers report finding a tile plugged with herbaceous roots in low-lying areas or along stream corridors. The usual cause is reed canary grass, an aggressive non-native plant naturalized in the Iowa landscape that is not seeded in prairie plantings.