Rice straw: the slow burnout
Dr. Gary Incaudo, a Chico allergist, says he can see it coming whenever there’s an increase in particulate matter, be it from agricultural burning or forest fires. “You know that within a week they’re going to be sick,” he said.
“There’s no doubt that air pollution factors influence the health of people who have respiratory problems,” he said. The tiniest bits of matter get in the airway, even binding themselves to allergens in the air, and especially affect those who already have allergies or asthma.
“It was particularly bad the last couple of weeks,” he said.
Regulators try to match burning to weather conditions, but “it does have potential to cause problems if we have unanticipated wind shifts,” explained Jim Waggoner, assistant air pollution control office for the county’s Air Quality Management District (AQMD).
The rice industry is at the end level of a phase-down designed by legislators to improve air quality by limiting the burning of rice straw.
If a grower wants to burn his fields, the county Agricultural Commissioner must certify that disease—usually stem rot or aggregate sheaphspot—is present there. Then, the grower gets on a “ready to burn” waiting list with the AQMD.
Even with those restrictions, a grower can burn only up to 25 percent of his total planted acreage, and the valleywide total can’t exceed 125,000 acres.
Incaudo, who keeps track of air quality statistics, said the regulators should “better-choose the days that are safe to do the burning.” Several days recently, the particulate matter exceeded government standards, but since the numbers are averaged over a 24-hour period, they look “a bit misleading,” Incaudo said.
Paul Buttner, manager of environmental affairs for the California Rice Commission, said the industry is dedicated to complying with the new rules, even though it would be much cheaper—only $3 an acre—to burn the straw. Some growers are incorporating the rice straw back into the soil, which costs $43 an acre, and hoping there will be soon be a demand for the straw—as erosion control, animal feed or fuel. But in the meantime baling straw costs $80 an acre.
The rice straw burning is expected to continue until the November rains and then start up again in January or March, Waggoner said.