Valley residents aren't the only ones wilting from triple-digit temperatures these days. The excessive heat is troublesome for field workers, livestock animals, vineyards and fruit trees.
Above-average temperatures can cause tree fruit to ripen slowly, dairy cows to produce less milk and workers to harvest in potentially dangerous conditions.
During the past 11 days, the temperature has hit triple digits eight times, including two days of 108 degrees. The average temperature this time of year is in the upper 90s.
"When it gets really hot, things just slow down," said Jim Simonian, president of the Fowler-based Simonian Fruit Co., a grower, packer and shipper of tree fruit and grapes.
To protect workers from heat illness, Simonian says his field crews will stop working when the temperature hits 100 and above. The state also has strict guidelines that require employers of outdoor workers to provide shade, access to cool water and training to spot heat-related illnesses.
"When it gets real hot, everyone goes home," Simonian said. "We don't get as much harvested, but we also don't want anyone to become sick. That's our biggest concern."
During the highest temperatures, fieldworkers typically will start at dawn and work until about early afternoon.
Farmworker advocates urge employers and state regulators to enforce the heat illness rules.
"Right now we have not heard of any problems," said Armando Elenes, United Farm Workers national vice president. "But sometimes people are too scared to say something. We want employers to follow the law."
State officials say inspectors have been out in the Valley's fields and have not found any major violations.
"Cal OSHA is conducting heat inspections especially in Fresno and other areas where there is excessive heat," said Erika Monterroza, spokeswoman for the Department of Industrial Relations.
For trees, vines and cows, the heat poses other challenges.
In the worst cases, thin-skinned fruit such as nectarines and plums can suffer from sunburn and the fruit can begin to break down internally.
"It just cooks from the inside and gets brown," said John McClarty, whose family owns and operates HMC Farms in Kingsburg. "But so far, we have not seen any of that in our fruit."
Trees and vines can go into a dormant-like state when daytime highs hit triple digits for an extended period. As the trees and vineyards shut down, the fruit will mature more slowly.
"On really hot, hot days, the grapes will go into shock and just shut down," said Ray Jacobsen, an Easton-area grape farmer. "And if it is severe enough, you will see some shriveling of some grapes."
Jacobsen said it is important for farmers to keep a good canopy of leaves on their vines to protect against the heat.
Dairy farmers are paying close attention to their cows, making sure they are not under heat stress. Many use a combination of fans and misters in stalls to keep animals cool. The hotter it gets, the less milk cows will produce. A slight drop in production during July is normal.
Dairy operator Joey Airoso of Pixley said farmers don't want a repeat of 2006, when scorching temperatures and high humidity killed thousands of dairy cows in California.
"We lost 66 cows in 10 days," Airoso said. "The problem back then was that the nighttime temperatures did not cool down and the cows did not have a chance to recover from the heat."
So far, Airoso said, evening temperatures have been mild, ranging from the low-to-mid 70s.
He is slightly concerned about the forecast for next week. Triple-digit temperatures will return on Sunday and continue to Friday. Monday's high is expected to hit 107.
"The forecast does not look good," Airoso said. "So we will do everything we can to keep our cows cool."
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