Local farms fare well in heat wave

As summer gives way to fall and temperatures begin to decline, many are wondering what impact this summer’s heat has had on agriculture, especially when contrasted with the wet, drought-ending winter that preceded it.

According to weatherag.com, Porterville has recorded 56 days with a high temperature of 100 degrees or higher this summer — 19 more than 2016 and 20 more than 2015. Statistically, 2017 has been the hottest summer on record for Porterville since 2006.

While the high temperatures have made this past summer uncomfortable for Central Valley residents, the region’s crops have endured the worst of the heat with relatively little damage. Other than some sunburn damage around the edges of citrus groves, which happens every summer, crops around Porterville have not been adversely affected by this summer’s heat wave.

“Extended heat periods take a bigger toll on employees than the trees,” said Gary Laux of Laux Management in Porterville. He also noted that heat plays a large role in the sweetening of citrus fruit, part of what makes Central Valley’s navel oranges so successful.

Scott Borgioli, chief meteorologist with weatherag.com, noted that while the Central Valley has had more 100-degree days than average this summer, there were few instances of consecutive days with maximum temperatures of 105-110 or higher, which can pose considerable risks to crops as trees begin dropping fruit to survive.

Growers have also benefitted from higher than average rainfall and snowpack in the Sierra Nevada, which has enabled them to sufficiently irrigate crops to offset evaporation and heat stress, unlike recent drought years.

In fact, according to Tricia Stever-Blattler of the Tulare County Farm Bureau, this summer’s heat wave has been less of an issue for growers than the flooding experienced around the Valley this spring.

The dairy industry, however, is far more susceptible to losses from high temperatures. While milk production from dairy cattle normally dips during summer months, extreme temperatures cause heat stress and vulnerabilities in livestock, especially among younger and older populations.

In 2006, a two-week period of extreme high temperature coupled with high humidity killed thousands of dairy cattle across the Central Valley.

Dairy farmers have learned from recent history and have upgraded their facilities with misting systems and blowers to keep livestock cool.

“[Dairy farmers] experienced a high mortality rate among dairy cattle during the heat wave of 2006, which led to new safeguards,” said Anja Raudabaugh, CEO of Western United Dairymen. “Over the last 10 years they have invested in cooling technologies that has better protected animals, even in extreme heat waves.”

As a result, local dairies have lost some cattle during this summer’s heat wave, but the cooling improvements have minimized those losses.

For those who are wondering if last year’s rainfall signals a favorable change and an end to the drought, there are conflicting theories regarding the upcoming year.

“I am concerned about the upcoming water year in terms of precipitation based on long-range forecast models,” said Borgioli.

He noted that some forecast models call for average rainfall in the Central Valley, while others predict less rainfall than average.

Fortunately, last year’s rainfall not only equipped the local economy to face the summer heat, it has provided some cushion in case rainfall totals are lower than average this year and beyond. Borgioli stated that it would take, “several bad years (low rainfall) to get back to the ‘really bad’ status” of the recent drought.

Recommended for you