This year’s beet harvest in southern Idaho and eastern Oregon could set record highs for sugar content and yield, thanks in part to good growing conditions and limited disease and insect pressure.
Lab measurement of samples as of early October pegged average sugar content at 17.4 percent, Amalgamated Sugar Co. Communications Specialist Jessica McAnally said. Last year’s average was 16.84 percent.
Boise-based Amalgamated, a grower-owned cooperative, aims for 18 percent average sugar content company-wide, achieved just once previously, she said. The number represents the percentage of sugar in the beet, which contains mostly water.
Average sugar content was expected to move higher barring bad weather, McAnally said. Beets store more sugar in their roots as harvest progresses and air temperatures drop, though heavy rain can prompt the plants to devote more energy to growing and less to producing sugar.
Boise received 0.95 inch of rain Oct. 9, the National Weather Service reported. Some spots in the region received over an inch.
“I’m afraid it will hurt sugar content going forward,” said Mitch Bicandi, a grower near Notus, in southwestern Idaho. “If we got another storm like this in the next week to 10 days, it would be really bad. We hope this is it.”
Before the rain, southwest Idaho beets showed higher sugar content than in the past, he said. “We’re just hoping they will hold.”
Bicandi, who plans to start harvesting Oct. 15, said growers whose harvest was underway Oct. 9 probably were shut down until late Oct. 10. But those who previously felt conditions were too try to dig may have seen some benefit from the rain, which amounted to around a day’s worth of irrigation, he said. Harvest typically wraps up by early November.
Beet growth and sugar production are helped by a long growing season with hot, dry days and cool nights. Disease risk rises when there is too much moisture in foliage.
“We have had an excellent growing season, and while we have seen some disease pressure, it has not been as bad as some years,” McAnally said. “We also have increased quality available in seed varieties available to our growers.”
On the pest and disease front, “overall we are pretty happy,” said Oliver Neher, plant health manager with Amalgamated. The Treasure Valley of southwestern Idaho and southeastern Oregon had a bit more Cercospora Leaf Spot than the company would like, but it was a “very normal” year for powdery mildew and Looper insects, without severe infestations, he said.
McAnally said the approximately 750 growers who comprise Amalgamated parent cooperative Snake River Sugar Co. will produce about 182,000 acres of sugar beets this year, about the same as 2017. Last year’s yield averaged 39.2 tons per acre.
Board President Duane Grant, who co-owns 4-D Farms in Rupert, in south central Idaho, said yield per acre is expected to be up from a year ago by 1.5 to 2 tons per acre, or around 5 percent.
“We believe we are going to set a yield record and a sugar-content record this year,” he said Oct. 9. “That is a credit to our growers, who have agreed to share with each other their cultural practices, reporting them into the company.” Such sharing “lets us learn from each other how to improve our collective crop.”
Nitrogen management is an example.
“Our growers have learned to very carefully analyze the fertility content of the top three or four feet of soil and apply just the right amount of fertilizer to grow the crop, but still allow it to consume available fertilizer and mature in a fertilizer-depleted environment,” Grant said. Beets maturing amid excess fertilizer grow root mass but do not accumulate sugar, he said.
Advances in seed genetics this decade played a major role in increasing the productivity of the plant, and in turn boosting sugar content and yield, he said.
Grant said the 2018 growing season featured a cool start, and a hot summer stretch with high temperatures on the upper end of their historic range — including “quite a few days of extreme temperatures over 100. We were concerned the heat would mineralize a lot of fertilizer in the ground.”
Mineralizing organic nitrogen would create an environment that is too fertile, prompting beets to add mass without accumulating sugar as effectively, he said. This did not happen to the extent beets gained mass and yield while losing quality, though “it did mineralize nitrogen. You could actually see sugar beet fields green up as we moved to the end of July into early August.”
Subsequently, temperatures dropped and wildfire smoke settled over southern Idaho for about three weeks, stopping nitrogen mineralization and allowing beets to mature properly, Grant said.
As for the Oct. 9 rain, he said an inch or more can reduce sugar content as beets soak up water, which also may add to transport and processing costs.
McAnally said early “pre-pile” harvest started Sept. 4 in south-central Idaho, and east in the Upper Snake River region, so Amalgamated plants in Twin Falls and Paul could begin processing the new crop. In southwest Idaho, harvest began on a limited basis Oct. 1 and production at the 500-employee Nampa plant started Oct. 4.
The plants run year-round, and process sugar beets from fall to as late as March or early April.