Yucca is the genus name for about 50 different species of trees, shrubs, and plants that fall in the Agavaceae family. In general, the plants are evergreen with white flowers and firm leaves that are shaped like spears or swords. They are most often found in desert or arid regions of the Caribbean, South America, Central America, and North America. Although each species may be treated differently, the similarities between them, such as their native climate and the shape of their leaves, make them easy to group under the single category of yucca. Some types include Joshua trees, soaptrees, Y. elephantipes and Y. filamentosa.
There are several species of yucca that grow upright, similar to trees. For example, the Y. brevifolia, also known as the Joshua tree, grows primarily in the Mojave Desert and in Joshua Tree National Park in California. Although it has spiny, spear-shaped leaves and white flowers, like most varieties, it also grows quite tall. In fact, the species has been recorded to reach heights of more than 50 feet (15.24 m). Other types of yucca that appear tree-like include Y. decipiens, Y. filifera, Y. rigida, and Y. elephantipes.
Some species are more shrub-like. For example, the Y. elata, or the soaptree yucca, is an evergreen shrub that has long, narrow, spear-like leaves. Although it is possible for the species to grow to 10 feet (3.05 m) tall, most remain much shorter. The root and trunk of this species are commonly used by some Native Americans as soap, and the fibers of the leaves are often used to make woven baskets or even dental floss.
There are several species of yucca that do not have trunks and consequently appear more plant-like. For example, the Y. filamentosa is a trunkless species that has long, sword-like leaves. As with most species, it contains tall stalks with clusters of white flowers during the summer months. Other trunkless species include the Y. pallida and Y. arkansana.
Most species of yucca grow best in full or partial sunlight. In general, as long as the soil drains well, the plant should thrive. As long as there is enough light, some species, such as Y. elephantipes, even thrive indoors.
Although yucca is most often used as an addition to landscaping, many species are used for medicinal purposes. For example, Y. schidigera is often used as a source of antioxidants and steroids. It is sometimes used to treat arthritis and is often used in cosmetics. Y. glorioso has white flowers that are often used as an antifungal. In addition, Y. elephantipes has flowers that may be eaten and are considered to be quite high in calcium.