The ongoing California drought has ranchers desperate for inexpensive livestock feed while air quality protections limit rice straw burning, leaving the rice industry with an abundance of typically low-quality straw to unload.
Though it has rarely been done, UC Cooperative Extension advisor Glenn Nader says the situation could be a win-win for beef producers and rice farmers: special treatment of rice straw could make it a nutritious cattle food.
When rice straw dries, its value as a forage declines dramatically. For 15 years, UC researchers have been trying to figure out why, but the reason for the significant change is not currently understood.
"At one time, we thought the problem was silica in the straw," Nader said. "We grew silica-free rice. That didn't work. We thought it was the crystallinity of molecules in the straw. We parsed apart the plant, and we still don't know."
Ultimately, it was a rancher who suggested the scientists to put aside their desire to know why quality declines when rice straw dries and look for practical ways to get around it. Nader postponed his retirement to comply.
Normally, rice growers bale the straw two to four days after harvest. Nader and his colleagues instead baled the straw immediately after it exited the grain harvester. They stacked the green straw bales and covered them with a tarp to retain moisture and prevent spontaneous combustion. The result is a product they named "strawlage."
Though one key worry was mold, researchers found that treating the straw with propionic acid prevents fungus growth.
"We haven't figured everything out, but with the drought conditions as serious as they are, we feel the time is right to share our research with growers," said Nader, who is planning a meeting to discuss the process with California beef producers later this month.
"We invite producers to come to the meeting to see if this will work for their operations. Several producers who have already fed strawlage to their cattle will speak at the meeting about their experiences," Nader said.
"Our goal is to give producers information that will allow them to make rice strawlage during this fall's harvest."