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Plant roots are important. They take in nutrients that plants need to live and grow. They help secure plants and they help to prevent erosion – the loss of soil to wind and water. Roots are the subject of an exhibit at the United States Botanic Garden in Washington, D.C. It shows in great detail what is taking place underground. The exhibit is called “Exposed: The Secret Life of Roots.” Visitors see dried roots hanging on a display wall in a large room. Some are from native prairie grasses. Others are from crop plants like wheat and corn. All of the roots are dried. They are rolled up so they do not touch the floor. A few are several meters long. Susan Pell is science and public programs manager at the Botanic Garden. She says this unexpected sight sends a powerful message to the visitors: Roots are the foundation for life. They absorb nutrients for the plants to make sugars. And, she says, as a species, we depend on plants. The roots appear to be growing out of a wide picture of a farmer’s field. Visitors can also see some of the grasses outside the Botanic Garden. They are growing with garden vegetables like carrots and beets. Susan Pell holds a soybean plant to explain why farmers depend on roots. She says they have little nodules on them, which contain a bacterium, which fixes nitrogen. It makes nutrients available to the plant. Susan Pell hopes visitors leave with a new understanding of our natural systems and the need to protect them from environmental problems.
