In the sun-drenched fields of Arizona, forage crops form the quiet and essential powerhouse behind two of the state’s top agricultural commodities: dairy and beef. These crops sustain livestock across the Southwest, support export markets, and deliver environmental services that often go unrecognized amid debates over water and land use. Among them, alfalfa stands out as the most efficient and versatile. Its deep roots, nitrogen-fixing ability, high nutritional value, and remarkable yields in the desert climate make it indispensable. Arizona farmers harvest premium alfalfa up to 10 times per year—averaging at least eight cuttings—compared to just three or four in other parts of the United States. This productivity, paired with the crop’s ability to improve soil and support biodiversity, underscores why alfalfa remains core to our local food supply.

Forage crops broadly include grasses, legumes, and small grains grown for hay, silage, or pasture to feed dairy cows, beef cattle, horses, sheep, and other livestock. In Arizona, the list of commercially significant forage crops reflects our arid climate, irrigated production systems, and year-round growing potential. While alfalfa dominates as the premier legume hay crop, other forages complement it by offering drought tolerance, rapid growth during specific seasons, or lower input needs in rotations.

Regarding alfalfa, for the farm kid, fresh-cut alfalfa on a summer morning breeze is one of the most wonderful smells. It grounds those who immediately recognize these fresh aromas.

During our most recent “Farm Fresh” hour on KTAR’s Rosie on the House Show, we discussed Arizona’s amazing alfalfa and visited with Pinal County farmer, Nancy Caywood.

Key forage crops grown in Arizona include:

  • Alfalfa (Medicago sativa): The flagship perennial legume, non-dormant varieties thrive in the low desert. It provides the highest protein per acre and supports multiple cuttings annually.
  • Bermudagrass: A warm-season perennial grass widely grown for hay and pasture. It offers good drought tolerance once established and serves as a reliable summer forage option, though it yields less protein than alfalfa.
  • Sudangrass and Sorghum-Sudangrass hybrids: Fast-growing annual warm-season grasses ideal for hay, silage, or emergency forage. They tolerate heat and variable water better than many crops and provide high biomass during peak summer months.
  • Teff grass: An emerging annual warm-season grass prized for its fine stems, rapid growth, and excellent hay quality. It fits well into rotations, including between vegetable crops, and requires relatively low water and fertilizer inputs.
  • Small grains for forage (oats, barley, wheat, triticale): Cool-season annuals harvested as hay or silage. They provide winter and early-spring feed, often in mixes, and help suppress weeds or build soil cover.
  • Corn for silage: Grown in select irrigated areas for high-energy silage. It complements alfalfa in dairy rations but requires more intensive management and lacks the nitrogen-fixing benefits of legumes such as alfalfa.

These crops together create a resilient forage system tailored to Arizona’s conditions. Yet alfalfa remains the efficiency champion—delivering superior nutrition, soil benefits, and economic returns per acre. Its story begins thousands of years ago, proving its enduring value today.

A Forage Crop with Great History: Alfalfa Facts

Alfalfa represents a centuries-old history as a domesticated crop. According to archeologists, remains of this forage crop are more than 6,000 years old and have been found in Iran and all over the world. The robust history of alfalfa proves its stamina today.

The primary use of alfalfa is as feed for dairy cows, horses, sheep, beef, and other farm animals. In fact, for livestock producers, alfalfa is one of three key forage crops. Without it, many dairy cows would not receive the nutrition required.

Due to its high levels of protein content—among the highest per acre, compared to other forage crops—alfalfa has enormous feed value. And because it’s a legume—like peas and beans—it fixes nitrogen in the soil, rather than requiring it as a fertilizer. This natural process reduces the need for too many additional inputs, lowering costs and environmental impact while building soil fertility for future crops.

In Arizona and California, alfalfa fields yield more than twice as many tons per acre as the national average, due primarily to climate, water management, and other conditions. Nationally, alfalfa is one of the most commonly produced forage crops.

Specific Facts About Alfalfa’s Superior Efficiency

Alfalfa’s nutritional profile sets it apart from grasses and other forages. Extremely palatable for livestock, alfalfa adds valuable fiber to our livestock’s diets. It has a faster rate of fiber digestion than grasses (including corn silage). This allows the energy from fiber fractions to become available rapidly over 12 to 24 hours.

Alfalfa is high in protein. Protein is the most expensive component of most rations. Good-quality alfalfa runs 16 to 20% crude protein (CP), while corn silage is 8 to 9% CP, and most grasses are 12 to 14% CP (grasses may be somewhat higher if harvested when immature). A milking dairy cow needs 16 to 17% CP, and growing animals need 12 to 16% CP. Thus, alfalfa can go further in meeting the protein needs of animals than most other forages.

Beyond protein, alfalfa provides needed minerals. It contains a greater concentration of calcium, phosphorus, potassium, magnesium, sulfur, iron, zinc, and selenium than grasses. It is a good source of calcium for all animals, especially horses.

Alfalfa provides needed vitamins. Leafy, green alfalfa hay is unusually high in carotene, the precursor of vitamin A. Vitamin A is the most common beef-cow vitamin deficiency. Good-quality alfalfa hay can furnish all the vitamin A needs of beef animals. Alfalfa is usually a good source of vitamin E and selenium, depending on the soil’s nutrient status on which the hay was grown.

Additional practical advantages include alfalfa’s higher natural buffering capacity and higher fiber level than corn silage, which reduces the problem of ration adaptation when feed sources are changed. Overall, alfalfa promotes animal health through its high mineral and vitamin content. One Arizona alfalfa farmer, Nancy Caywood, captures alfalfa’s food supply chain link appeal perfectly: “Alfalfa is milk chocolate in the making.”

These attributes make alfalfa uniquely efficient. While bermudagrass or sudangrass may produce solid biomass in hot summers, they cannot match alfalfa’s protein density or multi-year stand life. Teff offers quick turnaround and fine hay, but alfalfa’s perennial nature and nitrogen fixation provide unmatched long-term value. Small grains fill seasonal gaps but lack alfalfa’s year-round productivity and soil-building capacity. Corn silage delivers energy but demands annual replanting and higher nitrogen fertilizer. In Arizona’s irrigated desert systems, alfalfa maximizes output per acre while minimizing external inputs.

Arizona Alfalfa: Climate Advantage and Economic Role

Arizona is an excellent place to grow alfalfa because of our favorable climate that allows for up to 10 harvests of premium quality alfalfa per year, averaging at least 8 cuttings (compared to 3 to 4 in other areas of the United States). Non-dormant alfalfa hay varieties are uniquely adapted to the low desert climates of central and southern Arizona and the adjacent region of California along the Colorado River. Again, unlike many other production regions in the nation, low desert alfalfa is irrigated and produces an average of eight cuttings every year. In the Midwest, it’s about 3 to 4 cuttings a year.

Alfalfa hay has been exported from Southern Arizona and Southern California deserts regularly since the early 1970s. Agriculture economies have almost always been subject to the free market fundamentals of supply and demand; produce where it is most feasible and deliver to where it is most valuable. It’s estimated that 15% to 20% of Arizona alfalfa is sold for export; the majority is grown for local consumption. The demand for alfalfa in multiple foreign economies is higher than in America, enough to pay to have it shipped thousands of miles across an ocean.

Only a small amount of the water used in producing alfalfa is exported. Most water is recycled as part of the water cycle, known as the hydrologic cycle. When you study and understand the hydrologic cycle, you understand that you can’t export water in the alfalfa crop.

Without Arizona’s alfalfa crop, we could not support our two top agriculture commodities: Dairy and Beef. The crop’s high yields—more than double the national average—translate directly into efficient feed production that keeps these industries competitive.

The Benefits of Arizona Alfalfa to the Southwest Ecosystem

As the southwest U.S. continues to endure the conditions of “megadrought,” or any other term that describes the shortage of water in our region, some are attributing alfalfa for some of this problem. The share of water going toward alfalfa hay production supports the dairy and livestock industry, only one link separating you and me from healthy nutrition. This is not the only fact about alfalfa growing in the region.

Alfalfa in the southwest ecosystem provides many environmental benefits: it is a rich habitat for wildlife; provides an environment for diverse beneficial insects; improves soil characteristics; fixes atmospheric nitrogen; traps sediments and takes up nitrate pollutants; mitigates water and air pollution; and provides aesthetically pleasing open spaces.

Alfalfa is known by farmers and scientists as a soil stabilizer because it’s a perennial legume, staying in the ground for several years: four to five. Alfalfa fields are important contributors to the biodiversity of agricultural systems by functioning as insectaries for beneficial insects, many of which are pollinators or natural enemies that play important roles in the low desert agroecosystem. Beneficial insects move from alfalfa fields into other crops, where they play crucial roles in pollination and biological control, according to Ayman M Mostafa, Ph.D., Director for Maricopa County Cooperative Extension.

Banking Water with Alfalfa

During robust rainy seasons, growers often ask about the impacts of too much rainwater on alfalfa. Mostafa and others show that during the winter, alfalfa can establish a “water bank” for the summer season. One of the practices in our desert environment is to apply more water to alfalfa during the winter to have a “water in the bank” for later. This practice does have some merit for fields with deep soil if irrigation water is in short supply during the summer. Subsoil moisture can contribute to yield and stand survival when alfalfa is stressed for water. Alfalfa is a deep-rooted crop and can take up water from depths of 8 feet or more. Subsoil moisture at depths of 20 to 30 feet has been reported to contribute to alfalfa survival in drought years. With an active weather cycle and above-normal expectations of rain during this winter when it does happen, growers are advised to avoid excessive water that might affect alfalfa crop growth, especially during the premium winter/spring cuts, according to Mostafa.

In Defense of Alfalfa and Why It’s Core to Our Local Food Supply

Alfalfa is often accused of using too much water (this is while we continue to improve our irrigation technology and reduce the amount of water we put on our crops). This legume crop typically stays in the ground for as long as 4 to 5 years while undergoing repeated cuts per season. In Arizona, we’re known to get as many as 10 cuttings in one year.

But did you know that the massive amounts of alfalfa you see across our farmlands are a wonderful sequester of carbon? Studies have found alfalfa sequesters very high amounts of carbon through its very deep root structure that can reach 10 to 15 feet, and its natural growth and maturation processes. And bonus! Because it can stay in the ground for so long, the added benefit alfalfa contributes to our climate is massive. Remember plants take in carbon and breathe out oxygen for us.

“This is the type of agricultural economy we have in Arizona, where approximately 2% of the population produces 100% of the food and fiber,” says engineer and Ag consultant Nich Kenny. “Simplistically, the legitimate accounting of the water utilized in the process of raising the agricultural products lies with the 100%, not just the 2%.”

Arizona farmers are stewards of the land, constantly innovating with precision irrigation, improved varieties, and sustainable practices. Alfalfa’s efficiency—high yields, nitrogen fixation, carbon storage, and biodiversity support—makes it far more than a water user. It is a vital link in the chain that feeds our communities, strengthens rural economies, and sustains the Southwest’s agricultural heritage.

As we face ongoing challenges like drought and market volatility, alfalfa and complementary forages will continue to anchor Arizona agriculture. By understanding their full value—from history and nutrition to ecosystem services—we honor the farmers who grow them and the animals that depend on them. The next time you see those vibrant green fields stretching across the desert, remember: they are growing more than hay. They are growing the foundation of our food system.

The full interview on Rosie on the House is embedded below.

Sources: Arizona Farm Bureau, the University of Arizona Cooperative Extension, and our dedicated forage farmers.