Northern Utah fruit growers spent Sunday night trying to shelter tender buds from freezing temperatures in the aftermath of Sunday's storm.
It appeared Monday morning that damage wasn't as serious as growers had feared, said William J. Alder, meteorologist in charge at the Salt Lake office of the National Weather Service."Maybe we lucked out. I don't think it looks too bad," he said. "Cache could have had a little damage, but I think damage in Utah County was minimal."
He said lows were 24 in River Heights and 25 in Providence, Cache Valley. In Utah County the thermometer dropped to 28 in American Fork, Lyndon and north Orem, 29 in Elberta and Genola and 30 in Payson. Salt Lake City had a low of 31.
The use of wind machines and helicopters by growers trying to prevent damage may have made some of those temperatures 2 to 4 degrees higher than they would have been otherwise, he said.
Anthony H. Hatch, Utah State University extension fruit specialist in Provo, said, "It got near critical temperatures in a few locations, but our analysis of the weather would indicate we had minimal damage if any at all." He said growers wouldn't be able to assess damage until later Monday, because it takes four to six hours of warm temperatures for damaged plant tissue to turn brown.
"The critical temperature is 29 degrees," Alan Riley, owner of Riley's orchards, Payson, said Sunday evening. "Any colder than that, and there will be damage. It's just a matter of how much. We could lose the whole sweet and sour cherry crops, the peaches, and a lot of the red delicious."
"It's times like this you wish you were in another business. Any other business."
He said when there is a spring frost, fruit farmers hope for a warm day before the storm and for overcast weather. Under those conditions, the earth releases collected warmth, which is trapped above the trees but below the clouds a thermal inversion. Large fans on 30-foot poles blow the warm air down to the orchard.
"But Sunday had a bitter north wind, and it was snowing pretty hard in this area. If the ground collected any warmth at all, it will be trapped under the snow."
Riley said he had positioned his few smudge pots (heaters) so the fans would circulate the warm air they produced.
"But most orchards got rid of their smudge pots when the cost of oil skyrocketed. The people without pots can only hope the inversion will protect them," he said.
He said fruit growers often destroy some buds to ensure fruit will grow large and uncrowded.
"But we like to do our own thinning, not have Mother Nature do it."
"It's just one of those things you face every year. It makes me nervous because we have a lot riding on our fruit crop it's our livelihood," said Robert McMullin, chairman of the Utah Farm Bureau Fruit Crops Advisory Committee. But McMullin said propane heaters and wind machines should help keep temperatures above the critical mark.
The next few days are critical, said McMullin. He tends 800 acres of peaches, cherries and apples at McMullin Orchards in Payson. "If we can make it through tonight we have pretty good prospects for a good crop."
Northern Utah growers said the weekend storm itself was little cause for concern, dusting new blossoms with snow but not reducing temperatures harmfully below freezing.
"In this last storm the snow level was pretty high up. I don't think it will do that much damage; if it does, I'll still have a good crop," said Moss Sumida, Perry, Box Elder County, who raises peaches, cherries and apricots.
Southern Utah growers have already been unlucky this year. Washington County growers in the southeastern region of the state lost much of their peach crop in a March 29 freeze, said Utah State University extension agent Steve Campbell.
"Our peaches are at about zero," he said.
Fruit trees can withstand brief periods of slightly below-freezing weather. But if temperatures drop below 26 degrees, fruit ovaries inside a tree's flower can freeze, said Hatch. If that happens there's no fruit.
"Every year we have to sweat it out," he said.
Some frost-related fruit kill can be advantageous for growers, said DelRoy Gneiting, head of the Utah Agricultural Statistics Service, thinning out blossoms that might otherwise overload trees.
Recent bouts of wind may have also hampered fruit production to some extent, Gneiting said. Wind discourages bees from pollenating fruit trees.
Alder said temperatures should be a little warmer Monday night in fruit-growing areas.