Many people confuse yuccas and agaves, two robust plants that grow around Flagstaff. They’re in the same family (Agavaceae) and both have evergreen sharp, pointed leaves.
The two can be distinguished by size and leaf shape. Our local yuccas, the banana and the narrow-leaf, can approach 2 feet in height, including their flower stalks. On the other hand, our local agaves are smaller, although they produce tall, lanky flower stalks. Yucca leaves are straight as arrows and adorned with many fibers. Agaves in contrast have curved leaves that lack visible fibers. So, to identify a yucca, look for straight leaves with curly fibers; to identify an agave, look for smoothly curved leaves without fibers.
In the Flagstaff area we see many banana yuccas (Yucca baccata) and sometimes its slender cousin, the narrow-leaf yucca (Yucca angustissima). Banana yuccas grow in warm areas in the greater Flagstaff area -- on the southern slope of Mt Elden, in Picture Canyon, and at Walnut Canyon and Wupatki National Monument. These handsome, durable plants are often used in landscape plantings, too. Look for them along the Flagstaff Urban Trail between Route 66 and the railroad tracks and in other public places.
Purple yucca buds begin to form in late springtime. By early summer, these buds open into large creamy flowers. Oblong fruits, which perhaps resemble bananas, follow the blossoms in summer. This cycle repeats for several seasons on any individual plant. Narrow-leaf yucca shares most of these characteristics with the banana yucca plants, but is less showy and less common.
Our local agave variety, Agave parryi, is sometimes called “century plant.” These large specimens prefer warmer climates than Flagstaff: you will find them in Sedona and below the rim of the Grand Canyon. Small populations have been reported in wild places around Flagstaff, but they are not common. Some Flagstaffians have planted agave parryi in their yards in south-facing rocky areas where they do quite well.
Mature agave plants (in their mid-20s) send up tall spikes, 6 feet or more. These spikes look like gigantic stalks of asparagus. From these stalks, side branches (panicles) develop, bearing red and yellow blossoms. The stalks topple over when the plant dies that year.
Beneath mature agaves, you might see “pups” that will replace the dead parent plant. Native Americans transplanted these pups to start agave plots near their homes. Hundreds of years later, those plots still exist near ancestral farming settlements in the Grand Canyon and the Verde Valley.
Hisot'sinom (Ancestral Puebloan) peoples cultivated banana yuccas in Picture Canyon and other settlements near Flagstaff. Yucca plants were useful for their edible fruits, as well as their fibers, roots and spines.
The latter two can be fashioned into a needle-and thread tool for sewing; ask an interpretive ranger at Walnut Canyon to show you an example. Fibers from banana yucca were used to make sandals, rope, baskets and mats, remnants of which have been discovered at Walnut Canyon and other sites in the Four Corners region. The sweet fruits were (and still are) harvested and eaten raw, baked, or dried. Native peoples also used the yucca roots, rich in lathery saponin, to make soap and shampoo. No wonder these plants were so highly regarded by ancient peoples.
Agaves were, and are, valued for their rich, starchy root, an important source of food in springtime when winter stores of corn and beans were depleted. Harvesting the roots and from mature plants and roasting them underground for several days results in a tasty meal.
Rangers of the Red Rock District of the Coconino National Forest sometimes host traditional agave roasts in springtime. At any time of year, they can tell you where to find rock art depicting blooming agaves. These petroglyphs and pictographs are evidence of how special these plants were to ancient people.
Both agaves and yuccas are pollinated by moths; hummingbirds also visit their flowers. Both plants serve as hosts for giant skipper butterflies.
I offer one last pointer that has too often been impressed upon me: plants in the Agavaceae family have very sharp leaf tips that can pierce denim and human flesh with ease. Tread with care when walking near these handsome plants.