Switchgrass: Bridging Bioenergy and
Conservation By Linda Tokarz September 13, 2007
An important part of the answer to the country's energy woes
could be blowing in the prairie wind, according to Agricultural Research
Service (ARS) plant geneticist
Casler. He has spent the past 10 years breeding switchgrass, an
eight-foot-plus native plant that was an integral part of the tall grass
prairies that once dominated America's Midwest.
As a breeder, Casler is mostly concerned with the plant's
bioenergy-friendly attributes, including its ability to accumulate large
amounts of biomass and tolerate environmental stress. Casler works at the
Dairy Forage Research Center in Madison, Wis.
Recently, he began looking at switchgrass from another
standpointas a restorer of once-pristine prairies. Historically, a
sprawling seas of grasses once stretched from Montana and the Dakotas down to
Texas, with pockets of prairie as far east as New York. Now, with much of this
land fragmented or altered, only a patchwork of remnant prairies remains.
Numerous federal, state and private conservation efforts are examining
how best to revive these vestigial prairies. But a question of genealogy always
arises: Which switchgrass varieties should be planted that will be in keeping
with a site's genetic legacy?
Some conservationists insist on using only long-established, local
varieties of switchgrass. Others argue that modern-day cultivars can
appropriately be used.
Along with ARS scientist
Vogel in Lincoln, Neb., Casler set out to bring clarity to this debate and,
hopefully, ease the task of grassland restoration.
After two summers spent trekking native Midwestern prairies, plucking
samples and sending them back to his laboratory, Casler discovered that today's
agronomically important switchgrass cultivars are nearly identical genetically
to their grassy ancestors.
The study's findings are good news for prairie restorers, who can
confidently tap a wider pool of switchgrass cultivars and local varieties for
conservation projects. And switchgrass growers can take satisfaction knowing
their fields still are, in many ways, symbolic of the country's rich grassy
more about the research in the September 2007 issue of Agricultural
ARS is the U.S. Department of
Agriculture's chief scientific research agency.