Wildfire Smoke

This picture was taken recently at Evans Farming located on North Butte Road in Live Oak. The farm grows almonds and rice.

Wildfire smoke doesn’t just affect local air quality, the region’s agriculture industry also is impacted by smoke-filled skies. 

Whitney Brim-DeForest is the county director of the University of California Cooperative Extension (UCCE) for Yuba and Sutter counties. She’s also a rice advisor for UCCE in Sutter, Yuba, Placer and Sacramento counties.

She said wildfire smoke impacts different crops in different ways.

“For rice, most of the impact would occur due to the solar radiation (light from the sun) being blocked, and slowing photosynthesis,” Brim-DeForest said. “If sunlight is severely blocked, it slows plant growth and can reduce yields.”

In 2018, the region saw reductions in rice yields on the northwest side of the valley in Glenn and Butte counties from fires in the Redding area.

“In 2020, the smoke occurred later in the season, and we did not see impacts on yield,” Brim-DeForest said. “Based on last year and the timing of the smoke this year, we do not expect to see impacts on rice yields.”

She said it’s not known whether smoke can affect the quality, taste or milling yield of the rice. Farmers can do little to address the impact of smoke on their crop.

“There can be negative health impacts on our workers, so it is important for everyone to wear N-95 masks when the AQI is above 150,” Brim-DeForest said.

Amber Vinchesi-Vahl is a vegetable crops advisor at UCCE for Sutter, Yuba and Colusa counties.

“Heavy smoke can delay tomato ripening schedules which means delayed harvest or more green fruit at harvest,” she said.

Franz Niederholzer, UCCE Orchard Systems advisor for Sutter, Yuba and Colusa counties, said almond crops have also been affected.

“The smoke has been a real issue in almonds as it has reduced solar radiation to the orchard floor and slowed nut drying on the orchard floor (after shaking) and so slowed operations, increases water stress, and increases the risk of ant damage (longer time on the orchard floor),” Niederholzer said.

When it comes to rangeland livestock, the smoke does not seem to impact forage quality, according to Dan Macon, a livestock and natural resources advisor at UCCE for Placer, Nevada, Sutter and Yuba counties.

He said it’s unknown if smoke impacts the animals’ health. The UC Davis School of Veterinary Medicine is surveying producers about the issue.

Sara Light, a UCCE agronomy advisor for Sutter, Yuba and Colusa counties, said she hasn’t heard of as many issues as last year when the smoke was a problem for most of August. She said it may be too early to tell how bad this season will be yet.

“Since it was a really hot summer, some field crops matured and were ready to be harvested earlier than expected,” Light said. “This may mean they avoided the risk of smoke damage.”

She said an indirect impact of wildfire smoke is that when a grower harvests a crop at a higher than optimum moisture, it will affect down-the-line processing. Options are limited in terms of how to respond to this issue.

“Please let your farm advisor know if wildfire smoke is affecting your harvest so that we can stay abreast of the impact of fires in our region,” Light said.

Sutter County Ag Commissioner Lisa Herbert reminded the ag community about the importance of protecting workers from smoke. She said through a partnership with multiple state agencies, her office has N-95 respirators for free to give to farmers and farmworkers. They are not available for the general public. Farmers can pick up N-95 respirators at the Sutter County Ag Department (142 Garden Highway, Yuba City). The office is open Monday-Friday from 8 a.m. to 5 p.m.

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