Evaluation of herbicides for napiergrass (Pennisetum purpureum Schum.) establishment as a crop and for control as a weed

Abstract

Napiergrass (Pennisetum purpureum Schum.) is renowned as having the highest biomass productivity among herbaceous plants, and is considered an optimum feedstock for cellulosic biofuel production. Studies indicate pendimethalin plus atrazine applied pre-emergence allows for consistently higher weed control, stem height, and dry biomass yields for establishment. Concerns about napiergrass weedy characteristics include its ability for rapid growth, robust root system, vegetative reproduction, and invasiveness to other parts of the world. Growth reduction data measured by CO2 assimilation indicates that hexazinone, glyphosate, and imazapic are effective at reducing napiergrass growth. However, field results indicate glyphosate to be the most effective for control. Further research is needed on other agronomic and environmental variables in Georgia before full scale production of napiergrass can begin.