Growing and Propagating Giant Miscanthus Grass for Biomass Production and Natural Resource Conservation

Project Overview

FNC10-806
Project Type: Farmer/Rancher
Funds awarded in 2010: $5,979.00
Projected End Date: 12/31/2011
Region: North Central
State: Iowa
Project Coordinator:
Co-Coordinators:
Dennis Kasparbauer
Kasparbauer family farm

Annual Reports

Information Products

Commodities

  • Agronomic: general hay and forage crops, grass (misc. perennial), hay

Practices

  • Animal Production: feed/forage
  • Education and Training: demonstration, extension, farmer to farmer, networking
  • Energy: bioenergy and biofuels, energy conservation/efficiency, energy use
  • Farm Business Management: new enterprise development
  • Natural Resources/Environment: carbon sequestration, biodiversity, hedges - grass, habitat enhancement
  • Production Systems: agroecosystems
  • Soil Management: soil analysis, organic matter, soil quality/health
  • Sustainable Communities: new business opportunities, public policy, social networks, sustainability measures

    Summary:

    First of all the robustness and hardiness of miscanthus was impressive. We were pleased to see the growth over the first two years and how well the grass was able to hold up against the drought conditions of year two. There is no question that giant miscanthus can be grown successfully in western Iowa.

    The level of effort involved to plant the miscanthus was extensive but reasonable. Any more labor requirements would be costly, but since planning only occurs once per field, the investment over time is reasonable. The labor required to harvest rhizomes is too intense for large plots and mechanical digging and collection would be required. This added expense may prohibit rhizome harvesting from loamy clay soils. Not being able to harvest rhizomes on a large scale greatly adds to the overall expense of miscanthus. If rhizomes can be propagated, harvested, and replanted, it reduces the unit cost of each original rhizome. Without harvesting rhizomes, the unit of all miscanthus plants is fixed and is a major expense for initial planning. It may be feasible for a custom operator to own and lease the proper equipment to do large scale planting and rhizome harvesting, but it would require hundreds of acres to justify such a machine.

    The mid population level of 12,000 rhizomes per acre would cost just under $5,000 per acre to purchase and plant. Using our process, this would also require three people for close to three hours of time to plant each acre in addition to the rhizome cost. Beyond a few acres of area to be planted, this process would quickly become time and cost prohibitive.

    From the establishment of the three plots, both the mid or high populations are recommended for quick establishment of miscanthus. The low population still did not fill in adequately after two years, and it is questionable how successful a harvest will be after year three on the low population plot. It is difficult to tell to what extent the drought stunted the growth of the miscanthus study, but it was clear the no real harvest could be expected from the entire field after both year one and year two. There were more small bunches of quality miscanthus to harvest after year two, but the ratio of sparse growth to hardy growth was still not at a desirable level. Regardless of the population, plant growth was successful. It will obviously take longer for the low population plot to completely fill in compared to the high population. Based on the first two years of growth, this is also why the medium population plot is ideal for plant spacing. We still expect to see more growth in years three and four if the plot will remain.

    The higher population plot was only feasible economically to perform rhizome harvesting. The ratio of dirt to move compared to the number of rhizomes collected is maximized in high population plots and this would be recommended for rhizome propagation. Even greater populations than what was studied could be feasible, or double rows as was suggested separately.

    We were not able to perform a full production harvest of the plot due to the very low quantity of grass that was produced after both seasons. Based on how the plots appeared to mature in late season and go dormant, we believe an early spring or late winter harvest would be appropriate. The grass was not dormant enough in late fall and early winter to perform a harvest, and the grass would be too moist.

    Based on the best areas in the plot, after year two, a five-ton per acre harvest could be expected with a good stand throughout the plot. We feel this is limited data to base a final estimation off of due to the significant drought that occurred during year two that significantly stunted the growth of the grass. This does show a reasonable harvest can be expected even in years of extreme drought, but is short of the expected 10-20 tons per acre production yield.

    The biomass market has not been mainstreamed in western Iowa at the conclusion of this grant. Cellulosic ethanol plants in Emmetsburg and Nevada Iowa have been commissioned and are under construction, but the market for biomass has not reached SW Crawford County. We were able to work with the local high school to donate biomass to the school to use for cellulosic ethanol experiments and to help educate the agronomy classes on alternative crops and biomass production.

    Following the planting of the miscanthus grass, the plot was left as a no-till, minimum disturbance plot. The grass grew from early spring to late fall and went dormant over the winter. The habitat that the grass creates would be very beneficial to small and large wildlife during the growing season. We determined that an early spring harvest is the most realistic method to cut and harvest the grass for processing. This would keep the biomass in the field the longest to allow for natural drying, but it would also leave cover available through winter for any wildlife. Depending on the final realized profits available from miscanthus, it may be a better economic and environmental option when holistically compared to CRP.

    Miscanthus grass is an environmental and sustainable crop that can effectively be grown on farmland in western Iowa. The economic benefits are yet to be realized as a valuable outlet market for the biomass has not yet been fully established in Iowa. Overall, the planting of one acre and maintenance for two years cost approximately $7000. The highest expense was the rhizomes required for planting. This cost alone was approximately $5500 an acre. The remaining costs would be reduced on a per-acre basis by including more acres in the operation. The only ongoing cost after the crop is established is the harvesting costs at the conclusion of each season.

    The option of propagating miscanthus rhizomes is one effective way to reduce the unit price of rhizomes. This option does require additional equipment, and takes significant time to propagate rhizomes for new growth. This time delay coupled with the fact that three years of growth is required to achieve a profitable crop makes the miscanthus cost prohibitive on high value Iowa farmland.

    If miscanthus is a viable crop option for some areas it could be an economical gain for a region, providing work planting and harvesting both the miscanthus grass and the rhizomes. The biomass could be converted to sustainable fuel replacements that also add to the increasing independence and sustainability of agriculture.

    Introduction:

    The Kasparbauer family farm is located just west of Aspinwall, Iowa, one half mile north of Highway 141 in Crawford County. It is part of the M and M Divide Resource Conservation and Development region. The farm’s total land measures over 700 acres and is used for traditional corn and soybean production in rotation with no-till practices. He remains very involved, lives on the farm, and in addition manages several large tracts of switchgrass for conservation and game and wildlife habitat management. His son, Randy Kasparbauer, graduated from Iowa State University where he performed research with biorenewable resources. Randy now works for John Deere and began farming biomass crops for renewable energy production in 2011.

    Together, the Kasparbauers feel that there is promise in being early adopters of biomass production. Several areas of the farm’s land are currently in the Crop Reserve Program (CRP); thus, it is desired to transition the land to dedicated biomass crops. This will be done by replacing switchgrass with a more resilient and productive plant, while still conserving the land resource with limited agriculture.

    The project was to grow and evaluate the cultivation of giant miscanthus grass on three 1/3 acre plots. The plot totaled one acre in area of the grass crop. The crop was grown according to conventional practice where herbicide control for weeds was performed, but was the only required pass. No additional fertilizer or tillage was done to the land following the planting of the crop.

    The crop was evaluated for two years. Soil samples were taken from each plot and biomass analyses were done on the crop. An expansion of the miscanthus is desired, but based on the initial two years of miscanthus crop performance, prime farmland should not be a target cropland for miscanthus.

    Project objectives:

    • Is miscanthus grass a feasible crop to be grown in western Iowa?
      Are the labor, mechanical, and financial needs of growing miscanthus feasible for a small- to medium-sized farming operation?
      Is growing miscanthus an environmental benefit that can be comparable to ground currently in a CRP program?
      How does planting density affect growth and propagation of miscanthus grass?
      Will miscanthus be able to be harvested at alternative times in a year, how early can the grass be harvested when grown in western Iowa, and what is a realistic harvest volume to expect?
      Is there an established market to sell miscanthus grass?

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.