All plants contain secondary compounds (SC) and many of these compounds are thought to set a limit on intake for herbivores especially when offered as monocultures. However, in small doses these compounds may offer health benefits for humans and other animals. For instance, resveratrol a polyphenolic compound present in grapes, wine, soya, and peanuts helps prevent heart disease and various types of cancer in humans. Condensed tannins reduce internal parasites and nematodes in ruminants, and enhance the absorption of amino acids in the small intestine.

Herbivores eat more and perform better when offered a variety of plants that vary in concentrations of different nutrients and secondary compounds. When plants are grown in monocultures, especially those bred to be low in SC, large amount of fertilizer, herbicides and pesticides are needed to maintain the stand. Plants often benefit from growing in mixtures and reduce the need for the inputs listed above.

USU graduate student, Andrea Handy, is interested in some agronomic as well as environmental factors that may effect concentration of certain SC. Andrea plans to investigate how the type of fertilizer (none, commercial or sheep manure), the effect of growing plants in monoculture or mixtures and the time of day (morning or afternoon) affects SC. She will be studying alkaloids in tall fescue and reed canarygrass, tannins in birdsfoot trefoil and saponins in alfalfa.

The research will be conducted at Utah State University. Fred Provenza, Professor, and Juan Villalba, Research Assistant Professor, both of the Department of Wildland Resources will oversee the project.