Alfalfa Weevil on Damaged Leaf

California is the #1 dairy state in the U.S. and one million acres of alfalfa are grown in the state. Alfalfa growers use herbicides to control weeds and insecticides to control key pests-the Egyptian and alfalfa weevils. Organic alfalfa growers do not have effective methods of controlling weeds and insect pests and they incur yield losses – particularly by harvesting early to avoid damage. A recent economic analysis from the University of California estimated that organic production of alfalfa is one ton less per acre which would mean a loss of one million tons of alfalfa if the entire state converted to organic practices.

“The Egyptian and alfalfa weevils are the most serious pests of alfalfa, causing yield and quality losses to the first harvest in late winter/early spring.

Most organic growers rely on early harvest to minimize weevil damage, but yields will be reduced.

The risks associated with the production of organic alfalfa hay should not be minimized. Weather and other risks are a continual concern for conventional growers, but organic growers face additional risks such as pest outbreaks that cannot be adequately controlled with organic methods.

Average annual yields in California range from 5.0 to 10 tons per acre with three to ten cuttings depending on location and alfalfa variety. Eight tons per acre over seven cuttings per year is common in the Central Valley. The crop in this study is assumed to yield 7.0 tons of hay per acre because yields of organic alfalfa are often slightly lower than conventional due to only partial control of many pests and weeds and the difficulty meeting the nutritional needs of alfalfa using solely organic sources.”

Authors: Rachael F. Long, et al.
Affiliation: US Cooperative Extension Farm Advisor, Yolo, Solano & Sacramento Counties
Title: Sample costs to establish and produce organic alfalfa hay California 2013
Source: University of California Cooperative Extension. 2013.