Tom Ellis, Alfalfa grower
Board member California Alfalfa and Forage Association
There will be patches of green this summer amid a seemingly endless golden brown landscape that symbolizes California’s fourth year of an ongoing drought. Alfalfa fields will provide some of the green to an otherwise monochrome palate.
Not only will alfalfa fields provide an aesthetic break, but the fields will be sanctuary for over a quarter of the 675 amphibians, birds, mammals and reptiles that reside in California. Sanctuary for great blue herons, snowy egrets, red tail hawks, pronghorn antelopes and the Swainson’s Hawk, which was listed as a threatened species in 1983 primarily due to the loss of habitat, to name just a few of the 182 species that regularly feed, seek cover and reproduce in alfalfa fields.
In Dr. Dan Putnam’s May 13, 2015 blog, Why Alfalfa is the Best Crop to have in a Drought, he points out a number of alfalfa’s benefits to the soil, water quality and ecosystem.
Alfalfa’s deep roots benefit the soil. The long alfalfa stand life gives the soil a chance to rest from frequent field crop rotations, helps provide nitrogen for subsequent crops and improves soil tilth. Alfalfa leaves behind nitrogen and improves soil structure for the crop that follows so farmers can apply less chemical fertilizer. Alfalfa provides for weed control reducing the need for herbicide in crops that follow in rotation after an alfalfa field.
Alfalfa’s high water absorption and deep roots also make it a valuable crop to manage water tables. Alfalfa is also commonly used in the Delta region and Imperial Valley of California, to draw down high water tables and to limit saline seeps.
The crop requires few inputs, as the plants fix their own nitrogen with 90 percent coming from atmospheric nitrogen. Alfalfa, more than most other crop species, has the ability to intercept nitrates from the soil. Nitrates are considered by the United States EPA to be a major water contamination problem in the US.
As Dr. Putnam points out alfalfa has a high salt tolerance and can utilize degraded water. Alfalfa has been used to mitigate several environmental problems that are a consequence of our industrial society, including absorbing nitrates from groundwater, recycling dairy or municipal wastes, and mitigating industrial compounds that could contaminate groundwater.
It is this combination of deep roots, ability to utilize rainfall early in the year, high water use efficiency, ability to survive droughts, salinity tolerance, and ability to give partial yields with as much as half of the irrigation water that makes alfalfa particularly valuable whether in times of drought or normal rainfall.
On the hot summer days to come as you enjoy your favorite flavor of ice cream, remember without alfalfa, it wouldn’t be possible for dairies to produce all that wonderful goodness.
