10 Things You Didn’t Know About Agave Utahensis

It was an important food source for indigenous Americans

Agave utahensis played a significant role in the diet of indigenous Americans, particularly those living in the desert southwest. It was harvested and roasted for thousands of years by various groups, including the archaic desert cultures, ancestral Puebloan, and Southern Paiute. The plant was especially important to the Southern Paiute, who relied heavily on it as a food source, particularly during the spring. Some researchers believe that the presence of agave in certain areas is a primary reason for the establishment of archaeological sites in those regions.

It is the northernmost and coldest hardy agave species

Agave utahensis distinguishes itself as the most cold-hardy and northernmost occurring species of the Agave genus. It has an impressive ability to withstand freezing temperatures, in fact, US Department of Energy research has shown that it is hardy to temperatures as low as -9 degrees Fahrenheit (-23 degrees Celsius). This resilience is a testament to its adaptability, enabling it to thrive in high elevations and endure months covered in snow. This species has shown a remarkable ability to survive and flourish in conditions that would be challenging for many other plants.

It has been investigated as a source of biofuel

Most crop plants in the world use one of two photosynthetic processes: c3 and c4. Both of these require stomas (little mouth like openings on leaves) to be open to intake CO2 during the day to photosynthesize. In desert environments, this leads plants to rapidly lose moisture through their stoma, thus most c3 and c4 plants suffer in desert climates and as a result of climate change. A third type of metabolism, called crassulacean acid metabolism, or CAM, allows stomas to only open at night to take in CO2, thus reducing moisture loss and allowing them to grow in hot and xeric desert conditions. CAM plants are being heavily researched because of their ability to withstand climate change.

Agave is a genus of CAM plants and so has been the subject of a large amount of research into its potential as a biofuel crop (alongside its other uses). Because agave utahensis is the most cold hardy agave, it specifically has been the target of research into its productivity as a biofuel plant by the Department of Energy.

Its flower stalks can grow six inches a day

Agave utahensis flower stalks exhibit impressive growth rates. These towering structures, which can reach between 10 and 15 feet in height within a single season, are known to grow as much as six inches in a single day. This fast growth rate has been confirmed through direct measurements. The plant is monocarpic, meaning it flowers once and then dies, with this massive stalk serving as its spectacular swan song.

In Japan, a legendary clone exists called Kagerou

Agave utahensis has been a collector’s favorite species in Japan for many years. At some point multiple decades ago, a collector brought a remarkable specimen, with very wavy spines, to Japan and propagated it, either through coring or natural offset production. He named that clone kagerou, or heat haze, a reference to the wavy heat lines that can be observed rising from the pavement on a hot summer day. Today, many sellers list plants unrelated to that original clone as Kagerou, incorrectly using it to merely refer to the characteristic of wavy spines, rather than the specific and legendary clone that it actually is.

It's being investigated for anti-cancer properties

Steroidal saponins are metabolites that plants produce in response to stress and recent research has found more than 20 different kinds of Steroidal saponins in agave utahensis that have been shown to be cytotoxic—that is, they kill cancer cells.

Steroidal saponins have been found in a number of traditional Chinese medicines and Western science has found that in addition to their anti-cancer properties, they also have antiviral antifungal, and anti-inflammatory properties and can stimulate the immune system.

In habitat, it forms clonal rings that can live hundreds of years

Agave utahensis is known to form clonal rings in its natural habitat, and they can live for an exceptionally long time. These rings expand gradually as the plant produces new clones around the original "mother" plant. Over time, these expanding circles of plants can persist for hundreds of years, creating a remarkable living record of the plant's existence in a specific location over the centuries.

Variation is a species trait

One of the first things many people notice about agave utahensis is its variability. Plants growing mere feet from each other can exhibit wildly different characteristics. In fact, some plants growing within areas traditionally considered “nevadensis” habitats have such long spines, many people call them “eborispina” if they’re shown photos without being told exactly where the plants are.

Legendary agave botanist remarked on this diversity, noting that utahensis grows “variable inflorescences,” meaning their flower stalks can occur in one of three different types of structures: racemose, paniculate, or spicate. He further noted the importance of variability to understanding the species: “With study of the natural populations, such variation becomes a species character, bringing the whole into perspective.”

It grows in sky islands

Much of agave utahensis’s habitat is in the Mojave, the driest desert in North America. but it doesn’t grow in the hot and dry desert valley floors, rather it primarily grows above 4,500 feet in the mountains where it is much cooler and there is more moisture.

Prior to the last glacial maximum, much of its range was markedly cooler and wetter, so utahensis had a contiguous range, across a much wider stretch of land than it occupies today. Analysis of rat droppings from the Grand Canyon area demonstrates that it used to grow at much lower elevations 20,000 years ago.

But as the climate warmed, populations became isolated in what are called “sky islands” up in the mountains, separated by miles and miles of dry desert “sea.” This means that for more than 10,000 years agave utahensis populations have been evolving in isolation from each other.

It's probably the result of a field hybridization between kaibabensis and another species

The variable inflorescence that Gentry noted is an indication that agave utahensis is probably the result of a recent field hybridization—long-existing species of agave generally only grow one type of flower. The utahensis subspecies kaibabensis (which only grows near the Grand Canyon) is the exception to this as it only grows paniculate inflorescences, which likely indicates that it is the oldest version of utahensis. It was probably during that cooler and wetter time, before the last glacial maximum 10,000 years ago, that kabiabensis and another species of agave, perhaps agave parryi or agave mckelveyana, although it is not known for sure.