Switchgrass is a relatively new crop in California. Putnam has four research trials under way, testing varieties from Ceres and Mendel Biotechnology, Inc.  He calls switchgrass and miscanthus the top contenders so far in his trials.

“The switchgrass yields, especially in the Central Valley, California trials, are quite impressive on good soils with irrigation,” Putnam says. “Yields have reached 18 tons per acre — some of the highest switchgrass yields recorded in the nation.”

He says commercial switchgrass yields in California could average 8 tons to 15 tons per acre. His research is also measuring switchgrass performance under deficit irrigation.

“Switchgrass may not need its full year-round water requirement,” Putnam says. “We have seen a 30 percent to 40 percent reduction in water compared to its seasonal demand and still generate reasonable yields. This is very encouraging, especially in California where water supplies are an ongoing concern.”

Hardimon says biomass crops generally require a minimum of 20 inches of water annually. The plants naturally have deep root systems. Ceres’ switchgrass varieties have root systems three times larger than the above-ground plant.

“This gives switchgrass a tremendous ability to survive in low water conditions where other crops could have difficulty,” he says. “It also accounts for the large carbon sequestration potential of the plants.”

Much of the growing interest in biofuels is spurred by the federal Energy Independence and Security Act of 2007, plus the adoption of new state energy standards.

The U.S. law, in part, requires taxpayer funding for increased biofuels production. Biofuels added to gasoline must total 36 billion gallons by 2022, up from 4.7 billion gallons in 2007.

The federal law requires that 21 billion gallons of the 2022 requirement be derived from non-cornstarch products, including cellulose ethanol.

As the many needs of a burgeoning world population continue to evolve, Hardimon says foreign governments are seriously evaluating climate change and weighing a stronger commitment to cleaner-burning fuels. There is strong interest overseas in U.S.-grown biomass exports, Hardimon says, including U.S.-produced biomass pellets for European countries and the United Kingdom.

How would the basic biomass production premise work for U.S. farmers?

They would grow biomass under contract to a company for conversion at a biorefinery for cellulosic ethanol or at a biopower utility for bioenergy.

Hardimon suggests biomass farmers choose a facility within 50 to 60 miles of the farm — the closer the better to reduce transportation costs.

Putnam urges farmers to cautiously investigate biomass and how it may fit into their diversification portfolio.

“The first thing to consider is whether a local market exists for the product,” Putnam says. “If you can’t completely answer that question, then treat limited biomass acreage primarily as an experiment.”

He urges interested growers to gain the assurance of at least a short-term market (several years) with a local buyer.

The biomass industry, as with any new venture, is experiencing growing pains and many in agriculture are watching to see how it develops.

The next few years should be an exciting ride for U.S. agriculture in terms of new opportunities in the energy sector.

cblake@farmpress.com