“The reality is, it does use some of the most water,” says University of Idaho (U of I) Emeritus Professor and Forage Specialist Glenn Shewmaker, speaking of alfalfa. With agriculture using more than 40% of total U.S. freshwater withdrawals in 2015 and hay and forage crops weighing in at 37% of U.S. irrigation water use, environmental groups and the media have been known to blast alfalfa producers for excessive water use.
It’s true that alfalfa is a long-living, cool-season plant, less water efficient than warm-season crops such as corn. But alfalfa’s lengthy growing season, which directly correlates with its high water use, also makes it a desirable crop both economically and environmentally. “If you think about spring wheat, it’s growing for three months,” says Shewmaker. “Alfalfa is growing for 10 months. But it’s covering the soil and keeping the soil biologically active. Also, its roots penetrate deeply, so it’s a great drought-tolerant crop.” What’s more, the entire above-ground herbage – rather than just the seedhead or root – is usable. On the basis of harvested matter, that makes it more efficient than many alternatives.
Near Mountain Home, Bergh Farms rotates an orchardgrass-alfalfa blend with corn, wheat and sugarbeets. “It gives our operation some diversity and gives the land a good rest,” says operator Dave Bergh.
That’s a rest from cultivation – on Bergh Farms, a piece of ground will stay in perennial forage for four to eight years – and also a break from intensive inputs. “It’s beneficial from the carbon footprint standpoint,” says Shewmaker. “With the help of rhizobial bacteria, alfalfa fixes its own nitrogen. Not only that, but it’s good for the next two crops.”
A profitable choice
Alfalfa also makes economic sense. “Growers gravitate to what works,” says Bergh. “We like to do things that are good for the ground and the rotation, but we have to think about economics.”
Bergh Farms originally began growing its alfalfa-orchardgrass mix on pivot corners for their own cattle. “Lots of people wanted to buy small bales,” he says. “Demand for the product seemed to grow and grow.” As it did, so did the farm’s forage acreage.
Although the Berghs’ small bales and grass mix particularly target the Treasure Valley horse market, straight alfalfa is “a pretty common crop around here,” says Bergh. “They’re catering to the dairies.”
Alfalfa is well suited to southern Idaho, as to much of the arid, irrigated West. The climate and alkaline soils resemble those of Central Asia, alfalfa’s place of origin. As long as it has water, it can grow all summer long (all year long, in some of the Southwest). Bergh Farms typically harvests three to four cuttings of hay per year. With water going on the alfalfa mix around mid-April and the last cutting in early October, says Bergh, water demand is greater than for corn or wheat but comparable to sugarbeets.
And if the water isn’t there? “If you’re short of water, [alfalfa] will go dormant, but you’ll still get something,” says Shewmaker. “If you plant corn, and you run out of water, you get nothing – and you still have to replant next year.”
Growth and conflict
Historically, agriculture has been a primary water user in the western U.S. “When communities developed in the West after water projects came in, they developed around cattle,” says Dan Keppen, executive director of Family Farm Alliance, an advocacy group dealing with large-scale, water-related issues in the Western states. “These communities were built up around an ag economy.”
However, the 21st century has seen massive urban land development demanding a larger share of water allocations. Then, too, increasing demand for out-of-stream water use has heightened the demand for water allocated to stay in river systems, for the benefit of environmental processes and key species. Water resources are strained to the max, with added stress from droughts and insufficient groundwater recharge.
Alfalfa, the “queen of forages,” is well suited to the soils and climate of southern Idaho and an important crop for many producers from a soil health standpoint. Photo provided by Glenn Shewmaker.
Increasing demand on a constant or even diminishing supply have led some water users to cast a side-eye at other uses. As a big user, agriculture catches its share of side-eye. “A lot of people see ag as a) a water guzzler and b) contributing to climate change,” says Keppen. Others view livestock as an inefficient use of resources. Combine those perspectives in a forage crop that uses an admittedly high proportion of irrigation water across the arid West, and you have an easy target.
A few statistics
But it’s not such an easy target when you consider its place in the economy and food production system. NASS estimates placed alfalfa’s contribution to Idaho’s economy at over $1.1 billion in 2023. It also helps support the state’s beef and dairy industries, with a combined herd of more than a million cows as of Jan. 1, 2024.
Of these, the dairy industry alone contributed nearly $3.5 billion to the state’s economy in 2023 in milk production. Idaho’s many dairy processing plants elevate the industry’s impact even further.
Although researchers say the industry’s dependence on alfalfa is lessening, not growing, alfalfa still represents over a quarter of harvested acres of hay and haylage crops, and more than 85% of production of hay and haylage crops in the state.
“Alfalfa is part of a food supply that’s healthy,” says Keppen. “The demand is there – and not just here [in the U.S.].” In 2022, average U.S. dairy product consumption was 653 pounds per capita, while beef was 59.1 pounds per capita. Worldwide consumption of both is projected to grow with both affluence and population, and U.S. exports of alfalfa show that the “queen of forages” is internationally valued for her role in filling that demand.
“Many policymakers view climate change as the number one global fear and priority,” says Keppen. “My board of directors is much more concerned with how we address the much more pressing and documented need to double the world’s food supply by 2050. Climate change is a concern we have to deal with, but the global hunger issue is much more tangible and serious.”
Water conservation and technology
With everyone feeling the water squeeze, producers – like everyone else – are looking to conserve water however they can. Some may choose to accept payments for unused portions of their water rights or convert acreage to less thirsty crops.
And although not imminent, perhaps water efficiency improvements are ahead. In the last few years, researchers developed a working genetic map for alfalfa. “There is the genetic potential to select alfalfa for different forage traits,” Shewmaker says. “There is the potential to select for water-use efficiency or drought tolerance.” However, such a project could take a decade or more.
Other improvements, such as those to irrigation systems, may provide more immediate results. “It’s a cost/benefit issue,” says Shewmaker of infrastructure improvements like drip lines. “Alfalfa is generally thought of as not a high enough value crop.”
But as water demands increase, says Bergh, some producers may begin to look past the high price tag on such systems. “If the cost of water keeps going up and up, we’ll have to improve efficiency.”
References omitted but are available upon request by sending an email to the editor.
