Yucca Tree Facts

Native American Culture

• Native American tribes and nations in the western United States, such as the Apache and Muscalero, used yucca plants for a variety of reasons. The flowers of many yuccas are edible for humans, including the banana yucca (Yucca baccata) and thin-leaf yucca, while the Spanish dagger (Yucca gloriosa) offers edible fruit. Yucca roots are useful as cleansing soap and laxatives to cure constipation. Native Americans created sandals and weaving material from fibers found in yucca plant leaves.

Varieties

• All yucca plants are evergreen -- their leaves do not fall in the winter -- and live in dry, arid climates. One of the most recognizable trees of the American Southwest, the Joshua tree (Yucca brevifolia), is a yucca plant. Joshua trees are also among the tallest yuccas, standing at 30 to 40 feet at maturity. Many yuccas grow in the Southeast United States. Among these species are the Spanish bayonet (Yucca aloifolia), Adam's needle (Yucca filamentosa), bear grass (Yucca smalliana) and weakleaf yucca (Yucca flaccida). Southeastern U.S. yuccas ae short and feature long, spiny leaves.

Disease and Pests

• Like most plants, yuccas are susceptible to disease and pest problems. Horticulturists are able to determine what a yucca's problem is by observing the plant's symptoms. If the plant's leaves deteriorate at their tips and edges, the yucca is most likely experiencing a high level of water scarcity or overexposure to sunlight. Yuccas also experience fungal problems, such as stem rot and Southern blight, which has a cotton-white appearance. Mealybugs, scales and weevils are the most common insect pests of yuccas. Mealybugs and scales chew on the plant's leaves, while weevils attack the yucca's canes.

Age

• Under the right conditions, yucca species live for a long time. The Mojave yucca (Yucca schidigera) is able to live past 200 years. Counting the Mojave yucca's leaves and measuring its height are two ways of determining the plant's age. The Joshua tree does not have growth rings to provide information about its age, but the tree's height is the primary determinant of its maturity. Fully mature Joshua trees may be 800 to 1,000 years old, according to the San Francisco State University Department of Geography.