|RANDALL, BRYAN - University Of Missouri|
|HEATON, EMILY - Iowa State University|
|MYERS, DAVID - University Of Missouri|
|THOMPSON, ALLEN - University Of Missouri|
Submitted to: North Central Extension Industry Soil Fertility Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/1/2014
Publication Date: 11/19/2014
Citation: Randall, B., Kitchen, N.R., Heaton, E., Myers, D.B., Thompson, A. 2016. Nitrogen Management of Bioenergy of Miscanthus on Claypan Soil Landscapes. In: North Central Extension Industry Soil Fertility Conference Proceedings, November 19-20, 2014, Des Moines, Iowa . p. 141-146.
Interpretive Summary: Farmers are motivated by strong economic return, but also try to balance the return with the environmental impact on their land. Agricultural lands in many parts of central Missouri are less productive compared to other soils of the U.S. Midwest. This is due in part to a claypan layer of soil that is found 6-12 inches below the soil surface. This claypan causes high run-off, leading to erosion and nutrient loss. Miscanthus x giganteus is an emerging high-producing bioenergy crop with potential for high economic return while remediating environmental problems associated with degraded soil. The purpose of this research was to determine how nitrogen (N) fertilizer influenced the growth and yield of miscanthus when grown on Missouri claypan soils. The study was conducted from 2013-2014 on four central Missouri sites planted in miscanthus. We found that N fertilizer correlated with in-season plant greenness (as measured with chlorophyll content readings) early in the growing season but the effect of N fertilizer rate diminished by September. Further, only one site responded to N fertilization in 2013. This observed lack of response to N fertilization could be due to the ability of miscanthus to recycle nutrients from previous year’s growth, along with its ability to re-partition N into the most photosynthetic-active upper leaves throughout the growing season. Thus these preliminary results suggest little to no N fertilizer is needed when growing miscanthus on claypan soils. Additional years of study are needed to confirm this finding. This work will benefit farmers growing miscanthus since they have been asking questions regarding N fertilization to optimize miscanthus growth.
Technical Abstract: Bioenergy crop Miscanthus x giganteus has been well studied for its yield in Europe and certain parts of the US Midwest but little has been done to investigate Miscanthus production in settings found to be economically marginal for grain production. This study was conducted to determine nitrogen (N) requirements and yield potentials of M. x giganteus in degraded claypan soils. The effects of N fertilizer rates were investigated at four different locations in central Missouri on a Mexico series soil (fine, smectitic, mesic Aeric Vertic Epiaqualfs). In 2013, treatments of 0, 34, 68 and 134 kg ha-1 had no effect on the yield at two of the three locations. At the fourth site treatments of 0, 45, 90 and 134 kg N ha-1 also had no effect on yield. This lack of response could be due to the ability for miscanthus to recycle nutrients from previous year’s growth, along with its ability to re-partition N into the most photosynthetic-active upper leaves throughout the growing season. Higher N rates correlated with increased SPAD chlorophyll readings at all locations early in the growing season in both 2013 and 2014; however, little difference was observed in chlorophyll readings by September. These results will be used to develop N fertilization guidelines for farmers growing miscanthus.