April-May 2007 

The USDA NRCS Plant Materials Program newsletter for the conservation community 

Switchgrass: Possibly the Best Solution for America’s Energy Needs 

Awareness is growing about the untapped potential 

of switchgrass (Panicum virgatum) as a powerful 

(and renewable) energy source. And unlike ethanol 

produced from corn, which according to some

studies can actually contribute to air pollution, 

cellulose ethanol 

from switchgrass 

reduces greenhouse 

gases. And since 

many scientists 

agree that 

greenhouse gases 

are the cause of 

global warming, 

switchgrass may 

become more

important to energy 

production in the 

future than corn.

But there are still 

some major hurdles 

to overcome with 

the process of 

burning switchgrass 

for energy 

production. This is 

where the Plant Materials Program steps in. 

One of the main problems of using switchgrass as a 

biofuel has been the amount of ash which is created 

after burning it. The composition of the ash, which 

influences conversion technology, contains alkali 

metals (especially potassium). 

Potassium causes slagging and boiler fouling as a 

result of high temperature reacting with silica and

other minerals to create a gummy slag. 

“One option to improve the combustion properties 

of the biomass produced while burning switchgrass 

is to delay the harvest until potassium has been 

leached from the biomass,” said Joel Douglas, the 

Plant Materials Program’s Central Region Plant 

Specialist. 

“However, 

there is 

degradation of 

the biomass if it 

remains in the 

field too long.” 

To solve this 

problem, the 

Plant Materials 

Centers (PMC) 

at Knox City, 

Texas and 

Elsberry, 

Missouri, along 

with the USDA 

Agricultural 

Research 

Service and 

Mississippi 

State University are cooperating on a study to 

investigate how the timing of harvesting affects 

biomass yield and the biofuel-quality of 

switchgrass. 

‘Kanlow’ switchgrass is a productive variety for low-lying areas. 

The Program’s Long History with Switchgrass 

Several switchgrass cultivars labeled for biofuel 

consideration were evaluated and selected by the 

Plant Materials Program in the 1960s and 1970s for 

soil stabilization and livestock forage. USDA 

NRCS, along with several land grant universities, 

have conducted extensive research including variety 

trials over multiple locations to screen the best

Visit us: http://Plant-Materials.nrcs.usda.gov 

Plant Materials Program
adapted and highest yielding switchgrass. Most 

notable switchgrass cultivars receiving considerable 

attention through these and other biofuel research 

endeavors were: 

The United States Department of Agriculture (USDA) prohibits discrimination in all its programs on the basis of race, color, national origin, gender, religion, age, disability, political beliefs,

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information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD).To file a complaint of discrimination, write the USDA, Director, 

Office of Civil Rights, Room 326W, Whitten Building, 14th and Independence Avenue, SW. Washington, D.C., 20250-9410 or call (202) 720-5964 (voice or TDD). USDA is an equal

opportunity provider and employer. 

Visit us: http://Plant-Materials.nrcs.usda.gov 

• ‘Alamo’ released in 1978 by the Knox City, 

Texas PMC 

• ‘Cave-in-Rock’ released in 1974 by the 

Elsberry, Missouri PMC 

• ‘Kanlow’ released in 1963 by the 

Manhattan, Kansas PMC 

More than Just Switchgrass for Energy 

The Plant Materials Program has identified other 

potential energy producing biofuel crops include 

giant miscanthus (Miscanthus x giganteus), big 

bluestem (Andropogon gerardii), Indiangrass 

(Sorghastrum nutans) and alkali sacaton (Sprobolus 

airoides) Studies to evaluate them will be

established this year. 

nitial harvest will begin at seed maturity then 

sequential harvests will be made at 6 week 

intervals. In addition to biomass yield, fuel quality 

parameters will be collected to determine suitability 

for direct combustion conversion. 

PMCs outside the natural range of switchgrass (and 

other high yielding warm season grasses) are 

considering evaluating several cool season grasses, 

such as blue wild rye (Elymus glaucus) and tall 

wheatgrass (Thinopyrum ponticum) for biofuel 

potential. Studies are expected to begin in 2007. 

“We anticipate that the results of this cooperative 

research will provide information on the acceptance 

of other species for biofuel consideration and refine 

agronomic management technologies for further 

advancement of switchgrass and other grasses as a 

biofuel crop,” said Douglas.

Contact: Joel Douglas joel.douglas@ftw.usda.gov 

Taking the Next Step Using Switchgrass 

for Energy Production 

The Chariton Valley Biomass Project has been 

testing the effectiveness of ‘Cave-in-Rock’

switchgrass at a coal burning plant in Ottumwa, 

IA. The process consists of a 5 percent mixture of 

switchgrass and 95 percent coal. Approximately

11 tons of switchgrass is consumed every hour. 

The environmental benefits include emission 

reductions and substantially reduced sulfur 

dioxide release. The coal plant is currently 

offline to test for slagging of equipment because

of the use of switchgrass. The test results are 

expected by this fall.

Contact Plant Materials Specialist Jerry Kaiser 

jerry.kaiser@mo.usda.gov

A production field of ‘Cave-in-Rock’ switchgrass. 

Some Interesting Facts about Switchgrass: 

Why It’s Making Some 

Impressive Amber Waves 

Switchgrass has been designated by the U.S. 

Department of Energy as a model biomass crop 

because of the following attributes: 

• High biomass productivity over a wide 

geographic area 

• Commercially available cultivars 

• Planting and harvesting is compatible with 

conventional farm equipment 

• Low water and nutrient requirements 

• Suitable for marginal arable land 

• Multiple environmental benefits (soil erosion, 

carbon sequestration, wildlife habitat, water 

quality)

Our Mission: Develop and deliver plant-science technology to meet the nation’s natural resources conservation needs.