Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: February 10, 2012
Publication Date: February 21, 2012
Citation: Mitchell, R., Schmer, M.R. 2012. Switchgrass harvest and storage. In A. Monti (ed.) Switchgrass: A valuable biomass crop for energy (Green Energy and Technology). pp. 113-127. Interpretive Summary: Switchgrass is native to the North American tallgrass prairie and is broadly-adapted to habitats east of the Rocky Mountains. The USDA location in Lincoln, Nebraska, USA has been conducting switchgrass research continually since 1936, so switchgrass is not a new crop. However, switchgrass for bioenergy is more recent, and over the past 20-years best management practices have been developed for switchgrass biomass energy production. Switchgrass for bioenergy has not been adopted on a large scale, so production scale information on switchgrass harvest and storage is limited. However, large quantities of switchgrass biomass will need to be safely stored on a year-around basis to supply a cellulosic biorefinery, which are expected to keep only a 72-hour feedstock supply on site, with the remaining feedstock to be stored at the edge of field or at satellite storage facilities. Extensive research, as well as a history of harvesting hay crops for livestock in many agroecoregions, makes harvesting and preserving switchgrass for bioenergy feasible at the landscape scale.
Technical Abstract: The feedstock characteristics of the conversion platform will influence the optimal harvest and post harvest management practices for switchgrass. However, many of the harvest management practices are tied to plant phenology and will be similar across platforms. Proper harvest and storage of switchgrass will help provide a consistent and high-quality feedstock to the biorefinery. Bioenergy-specific switchgrass strains are high-yielding and in most cases can be harvested and baled with commercially available haying equipment. Many options are available for packaging switchgrass for storage and transportation, but large round bales or large rectangular bales are the most readily available and are in use on farms. Large round bales tend to have less storage losses than large rectangular bales when stored outside, but rectangular bales tend to be easier to handle and load a truck for transport without road width restrictions. Although there is limited large-scale experience with harvesting and storing switchgrass for bioenergy, extensive research, as well as a history of harvesting hay crops for livestock in many agroecoregions, makes harvesting and preserving switchgrass for bioenergy feasible at the landscape scale.