Dr. Parry Kietzman is a research scientist in Virginia Tech’s School of Plant and Environmental Sciences. Here she describes a new experiment aimed at improving Southeastern grazing lands to improve cow health, provide habitat for pollinators, and conserve plant biodiversity. A member of the bee-friendly beef team since 2020, her work focuses on the ecology and conservation of pollinating insects.
Across the world, pastures account for over 20% of the Earth’s land surface, an area roughly the size of Africa. Many of these pastures were once species-rich meadows, prairies, and woodlands that offered abundant and diverse food resources for pollinators, but are now limited to a handful of species that provide forage for grazing livestock.
Pollinating insects such as bees, flies, butterflies, moths, and beetles are currently in crisis, as habitat loss from development, intensive agriculture, and other human activities have diminished the food sources and nesting sites they rely on. The conservation of pollinators native to each particular region is especially important, as many plants depend on native specialists for pollination. The widely-kept, domesticated, European honey bee (Apis mellifera L.), though of great importance to modern agriculture, is often not successful or at least not as efficient at pollinating certain plants as the bee specialists that coevolved alongside each particular species. Landscapes rich in a diversity of plant species native to that location are therefore needed to provide habitat for these native pollinators.
Researchers at Virginia Tech, the University of Tennessee, and Virginia Working Landscapes are currently collaborating on a multi-year rehabilitation project to plant native North American prairie grasses and wildflowers in cattle pastures in Virginia and Tennessee. The project is based on the idea that a landscape can be supportive of healthy cattle production while at the same time providing ecological niches for pollinating insects. Bringing back diverse food sources for pollinators in pastures, however, presents some significant challenges. First, the plants must not be harmful to livestock that may graze on them. Second, they must be hardy and practical to establish in new and existing pastureland. Finally, they should be native to the region in which they will be planted, as this will be most beneficial to that region’s native pollinators and help prevent the accidental introduction of invasive species.
Our team is currently working to identify and successfully establish seed mixes that thrive in Virginia and Tennessee without becoming excessively weedy or crowding out grasses grazed on by cattle. Once established, pollinator diversity and abundance will be measured in plots with and without wildflowers introduced. Herds of cattle grazing in the pastures will also be monitored for health and body condition.
Results from this study, including critical information about best practices for establishing the seed mixes, optimal grazing regimes to promote blooms, and wildflowers as forage will be disseminated to growers and other stakeholders through extension services such as published fact sheets, protocols, and workshops. This foundational work will help inform researchers and land managers around the globe how to transform pasturelands into landscapes that can help save our pollinators.
For more information on this ongoing study, visit the team’s website: beesandbeef.spes.vt.edu.