FRESNO, Calif. (KFSN) -- This week's high heat has some valley farmers a little concerned.
Heat waves are common during the summer. The sun helps sweeten fruit, but at the same time, too much of it can damage oranges.
The white spots on oranges and leaves of trees are meant to protect the fruit from sunburn. Orchards at Fresno State were sprayed last month when the citrus started to develop.
Orchard Manager Rob Willmott explained, "You put it on when it's about the size of a nickel and as the fruit swells up, as it gets larger, that sunblock continues to expand with it protecting the fruit."
Willmott showed us how the sun can damage oranges. The fruit will be fine inside but consumers won't buy it because of the sunburn spot. He said, "So you can already see the yellow turn to brown and it will just keep getting darker and darker."
After harvest, cherry trees were also sprayed with sunblock. So were walnuts.
Willmott said of the spray, "it's kaolin clay which is a natural form of clay that is mined. it's an all-organic material."
Willmott will keep a close eye on the citrus. If spots show up on too many fruits the trees will need a second application of sunblock. "You really see where you put it on and where you missed."
Crews were also keeping tabs on soil moisture to make sure plants and trees aren't too stressed.
Heat wave has some Valley farmers concerned