Dry Matter, Carbon, and Nitrogen Accumulation of Four Great Plains Grasses

Abstract

ABSTRACTNative North American warm‐season bunchgrasses have the potential to provide both forage and cellulosic bioenergy in drier regions of the southern Great Plains. Almost no information is available on the potential accumulations of many of these species under forage, bioenergy, or combined system harvests. Multiflower false rhodesgrass (MFR; Chloris pluriflora Fourn.), pink pappusgrass (PPG; Pappophorum bicolor Fourn.), shortspike windmill grass (SSWG; Chloris × subdolichostachya Müll. Berol. (pro sp.) [cucullata × verticillata]), and plains bristlegrass (PBG; Setaria vulpiseta Scribn. and Merr.) were harvested during 4 yr at Stephenville, TX, USA. Seedlings were transplanted into a Windthorst sandy loam soil fertilized in Year 1 with 0 or 67 kg N and P ha−1 yr−1 plus 67 kg N ha−1 yr−1 in the spring of Years 2 to 4. Fertilizer improved N and dry matter (DM) accumulations (P ≤ 0.05) except for SSWG and improved (P ≤ 0.05) accumulations of October regrowth following July harvest in greater rainfall years. Multiflower false rhodesgrass produced greater (P ≤ 0.05) accumulation the first year (up to 4.38 Mg ha−1) while PPG had the most consistent accumulation across years with variable precipitation. Results indicate that MFR and PPG bunchgrasses native to the North American Great Plains have potential for bioenergy or forage and bioenergy production systems.