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ARS Home » Plains Area » Temple, Texas » Grassland Soil and Water Research Laboratory » Research » Publications at this Location » Publication #315512
Title: Effect of intercropping hybrid poplar and switchgrass on biomass yield, forage quality, and land use efficiency for bioenergy production

Author
item KIMURA, EMI - Washington State University
item FRANSEN, STEVE - Washington State University
item Collins, Harold
item STANTON, BRIAN - Greenwood Resources, Inc
item HIMES, AUSTIN - Greenwood Resources, Inc
item Smith, Jeffrey
item GUY, STEPHEN - Washington State University
item JOHNSTON, WILLIAM - Washington State University

Submitted to: Biomass and Bioenergy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/18/2018
Publication Date: 2/22/2018
Citation: Kimura, E., Fransen, S.C., Collins, H.P., Stanton, B., Himes, A., Smith, J.L., Guy, S.O., Johnston, W.J. 2018. Effect of intercropping hybrid poplar and switchgrass on biomass yield, forage quality, and land use efficiency for bioenergy production. Biomass and Bioenergy. 111:31-38. https://doi.org/10.1016/j.biombioe.2018.01.011.
DOI: https://doi.org/10.1016/j.biombioe.2018.01.011

Interpretive Summary: Land use efficiency can be maximized if an intercropping system is utilized to produce switchgrass (Panicum virgatum L.) biomass within the alleys between hybrid poplar trees (Populus spp.). Information is limited on switchgrass production and intercropping system in the Pacific Northwest of U.S. Switchgrass growth was reduced by intercropping with hybrid poplar. However, tree yield was not reduced in intercropped plots. As a result, land equivalent ratio based on cumulative switchgrass and hybrid poplar DM during the three years of the study was maintained at average of 1.6 in intercropped compared to 1.0 in monoculture plots. This indicates that 60 % more land would be required in monoculture system to produce the same amount of DM compared to that produced in the intercropping system.

Technical Abstract: Land use efficiency can be maximized if an intercropping system is utilized to produce switchgrass (Panicum virgatum L.) biomass within the alleys between hybrid poplar trees (Populus spp.). Information is limited on switchgrass production and intercropping system in the Pacific Northwest of U.S. Objectives of this study was to evaluate the effects of hybrid poplar trees on switchgrass yield and forage quality and to determine the land use efficiency in an intercropping system under irrigation. Three cultivars of switchgrass (‘Kanlow’, ‘Blackwell’, and ‘Trailblazer’) were planted in the alleys between hybrid poplar trees (Clones: OP367 and PC4) at Greenwood Resources, Boardman OR in 2011. Switchgrass growth was negatively influenced by hybrid poplar trees with mean leaf area index, tiller density, and switchgrass dry matter (DM) yield in the monoculture and intercropped plots to be 4.9 and 1.7, 383 and 69 tillers m-2, and 15 and 4 Mg ha-1, respectively, in the third year of this study. However, tree yield was not reduced in intercropped plots. As a result, land equivalent ratio based on cumulative switchgrass and hybrid poplar DM during the three years of the study was maintained at average of 1.6 in intercropped compared to 1.0 in monoculture plots. This indicates that 60 % more land would be required in monoculture system to produce the same amount of DM produced in the intercropping system. This study revealed that, despite the reduced switchgrass growth under hybrid poplar trees, intercropping hybrid poplar and switchgrass can improve land use efficiency for biomass production.