Miscanthus questions and answers

(Source: Adapted from Ohio State University and Penn State University)

Q: What is miscanthus? Why are farmers growing it?

A: Miscanthus is the genus name for 12 perennial grass species native to Asia. A close relative of sugarcane, this tall reed or cane-like plant was introduced to the United States as an ornamental plant in the 19th century.

Recognizing its growth potential and ability to withstand cold conditions and poor soils, it has become widely known for biomass production. Giant miscanthus (miscanthus x giganteus), a non-invasive hybrid of miscanthus sinensis and miscanthus sacchariflorus, is the species most commonly used for bioenergy.

The plant reaches heights of up to 12 feet and in research trials has shown to be among the highest-yielding perennial energy crops, producing an annual average of up to 8-12 tons per acre.

Q: Why Northeast Ohio and Northwest Pennsylvania?

A: There are many reasons. The major advantage is the potential acreage available for production. Miscanthus will grow on marginal soils, which allows fallow and marginal acres in northeastern Ohio to be placed in production (acreage will most likely not be on land already in corn or soybean production).

Another advantage is that northeastern Ohio was chosen by the United States Department of Agriculture as a BCAP (Biomass Crop Assistance Program) project area June 15, 2011. This program provides federal benefits to farmers who have transitioned part of their farm acreage to miscanthus production.

Q: How is it planted?

A: Miscanthus is planted using rhizomes (root growths) which make it more expensive to establish than other energy crops from seed. The planting rate is about 15,000 plants per hectare (6,000 plants per acre).

Planting is typically done in late spring after the last frost. Rhizomes are becoming more available but a specialized equipment agreement is needed for planting.

Q: How long does it grow?

A: Establishment of Giant miscanthus takes two to three growing seasons before a full crop can be expected. Weed control is essential in the first year and possibly the second year.

A critical establishment issue is frost kill during the first winter after planting. However, once it gets through its first winter, it usually survives subsequent winters and is weed free, as it tends to crowd out all other plants in the field.

Miscanthus has low nutrient requirements during establishment and has not shown much response to nitrogen fertilizers.

Q: What do you do with it?

A: While the current market is limited, giant miscanthus can be pressed into fuel pellets or biomass logs for combustion, or it can be used as a feedstock for cellulosic biofuel production. Non-energy possibilities for miscanthus include animal bedding, absorbents, and bio-based materials such as fiberboard.

Q: Is it profitable? How much does it cost?

A: The largest expense for establishing miscanthus is purchasing planting material. Assuming rhizomes at 10-25 cents each and about 6,000 rhizomes per acre comes to at a minimum of more than $600 just for plant material. Other planting expenses are similar to other row crops at about $400/acre. Harvest costs range from $300 to $500 per acre, depending on the type of machinery used. Depending on yields, break-even prices range from $40-80 per ton at the farm gate.

Q: What are the challenges?

A: As with any new crop, there will be a learning curve for farmers who will begin raising miscanthus. A second obstacle is that the miscanthus acreage will be planted through the use of rhizomes, which requires greater expertise during planting to manage weeds and water availability.

A third limitation is the typical harvest window for miscanthus is after a fall killing frost and before the emergence of the new shoots in the spring. Therefore, producers will need to work around the winter weather found in northeast Ohio.

Other limitations include limited planting material, and limited planting and harvesting equipment. Producers also need to keep in mind that miscanthus is usually not harvested until after the second year of growth, and stands are usually kept in place for 20 or more years.

Q: How can I learn more?

A: Ohio State University Extension in Ashtabula County has an extensive list of resources at www.ashtabula.osu.edu. Penn State University has information available at www.newbio.psu.edu. Aloterra Energy is available online at www.aloterraenergy.com.