“Our lab works with cover crop legumes, which take nitrogen from the air and trap it in their leaves,” explains Grossman (M.S.–'98, soil science; Ph.D.–'03, agronomy). “When a farmer kills these plants and puts the residue back into the soil, their cash crop—corn, for example—can use the nitrogen. We look at the decisions that farmers make throughout the legumes’ life cycle and how they affect soil quality and nutrient availability.”
Much of her research is applicable to both conventional and organic farming, but Grossman has always had an urge to make a global impact. “It was one of those light-bulb moments as an undergrad. Through agriculture I could take my biology knowledge and use it to help increase food access and availability.” Her research is particularly useful to farmers in developing countries, who don’t have ready access to synthetic fertilizers.
The idea may seem simple, but her research could affect one of Minnesota’s most valuable resources: water. “Synthetic nitrogen has been implicated as one of the biggest pollutants in the Mississippi due to the mismatch of crop uptake to nitrogen application and availability.” In contrast, legumes are broken down slowly, with the potential for crops to use legume nitrogen as soon as it’s available, avoiding its loss to bodies of water.
In addition to her research, Grossman sees her students as one of her biggest legacies. “I love working with the students and helping them tell the story of their scientific work. My only regret is that I don’t have twice as many hours in the day to work with them.” Currently she advises five graduate students and mentors several undergraduate students working in her lab. “I work really hard at developing good scientists—how to do the science, talk about it, think about it, and most importantly how their results might translate into policy. I want them to understand the potential global impact of their work.”
Her lab group worked together to pick out the strangest item in their lab space. Their final verdict? Hundreds of pee cups. “They are cheap, stack well and have nice, tight-fitting lids, perfect for nitrogen extractions from soils,” Grossman says with an almost mischievous smile. “It was either that or the farmer Santa Claus doll in our party drawer.”