The groundcover levels after corn (Zea mays L.) silage harvest are rarely adequate to prevent soil erosion, but most corn-growers do not plant cover crops due to time and cost limitations. Herbicide-resistant corn hybrids provide opportunities to control weeds and to utilize cover crops in previously unexplored combinations. Field studies were conducted in 1999 and 2000 at Dryden and Valatie, New York, USA, to determine the potential for managing existing quackgrass (Elytrigia repens [L.] Nevski) as a cover crop in herbicide-resistant silage corn.Three isolines of the corn hybrid, DKC493, were treated with glyphosate, glufosinate, primisulfuron, nicosulfuron or sethoxydim.Averaged over all site-years, the corn silage yields with glufosinate were similar to those with glyphosate. Glufosinate also resulted in a quackgrass ground cover greater than the 30% threshold for preventing soil erosion. Quackgrass could be managed as a perennial cover crop in silage corn-perennial forage dairy rotations in north-eastern USA.

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Tannins are plant chemicals that humans find useful in products as diverse as tea and leather. Why do plants produce these compounds? One possible answer is defense against pathogens and herbivores. In this series of laboratory exercises, student inquiry begins with a simple question: What happens to the multitude of leaves that drop each autumn? This inquiry brings students from the outdoors to the laboratory, where they observe differences in leaf decomposition rates and the natural abundance of bacteria and tannin concentrations in leaf tissues of red oak, white oak, and tulip poplar. In the process, students increase their understanding of plant chemistry, bacterial culture, graphing, and natural history, while experiencing the iterative nature of scientific inquiry.