Growers Prepare for First Alfalfa Harvest of the Season

It has been a race against time for alfalfa growers.

Weevil populations have been on the rise and alfalfa has been growing quickly, spurred by the unseasonably warm temperatures, including that 90 degree weather a week ago.

Field scout Carlos Silva says weevil counts are running 10 to 12 pests for every sweep of his sweep net. Those numbers are climbing closer to the treatment threshold of 18 to 20 bugs per sweep.

Alfalfa growers are nearing the first harvest of the season.

 “Some growers already have treated for weevils,” Carlos points out.

The Egyptian alfalfa weevil poses the most serious threat to the crop, according to University of California IPM. Adult females will insert their eggs in the alfalfa stems. The larvae will hatch and start feeding on the terminal buds and leaflets.

Growers need to focus on managing the pest before the first cutting of the season. UC IPM says: “Weevil management in alfalfa is focused on the period before the first cutting. Control options are insecticides and early harvest. Biological control is not effective at preventing economic damage in most areas because populations of natural enemies are not sufficient to provide control in the spring.”

Alfalfa is cut when the plant is about 24 inches tall.

Right now, alfalfa is about 18 to 20 inches tall – growers usually cut around the 24-inch mark. Carlos anticipates this year’s first alfalfa harvest to start in a week or two.

Meanwhile, cotton growers have been pre-irrigating their fields and starting to purchase their plant seeds.  A number of long-time cotton growers remain committed to the crop, despite the ongoing drought and water availability issues.

Cotton growers have been pre-irrigating their fields.

It’s too early to predict how the prolonged drought will affect cotton acreage this season. Last year, growers planted 213,000 acres of cotton, down 23 percent from 2013, according to the U.S. Department of Agriculture.  Cotton production fell an estimated 24 percent to about 730,000 bales.