Common Name: Spanish Bayonet

General Information

Yucca baccata is an evergreen shrub producing a rosette of spear-shaped leaves 30 - 100cm long and 2 - 6cm wide from a stem that is usually subterranean but can be up to 2 metres tall. The plant can form a cluster of up to 24 rosettes[].
The plant is harvested from the wild for local use as a food, medicine and source of materials. The roots of Yucca species are rich in saponins and have a wide range of applications. The plant is cultivated as a fibre plant in Mexico and Irag, and is often grown as an ornamental in gardens[].
Yucca baccata has a wide range, a relatively large population, and any declines are local and relatively small. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2020)[].

Known Hazards

The roots contain saponins[].
Although poisonous, saponins also have a range of medicinal applications and many saponin-rich plants are used in herbalism (particularly as emetics, expectorants and febrifuges) or as sources of raw materials for the pharmaceutical industry. Saponins are also found in a number of common foods, such as many beans.
Saponins have a quite bitter flavour and are in general poorly absorbed by the human body, so most pass through without harm. They can be removed by carefully leaching in running water. Thorough cooking, and perhaps changing the cooking water once, will also normally remove most of them. However, it is not advisable to eat large quantities of raw foods that contain saponins.
Saponins are much more toxic to many cold-blooded creatures, such as fish, and hunting tribes have traditionally put large quantities of them in streams, lakes etc in order to stupefy or kill the fish and make them easy to catch[].

Botanical References

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Range

South-western N. America - California, Nevada, Utah, Arizona, Colorado, New Mexico, Texas, northern Mexico.

Habitat

Rocky slopes, pinyon, oak, and juniper woodlands, grasslands, growing in a range of soil types; at elevations from 400 - 2,500 metres[].

Properties

Conservation Status	Least Concern
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Evergreen Shrub
Height	1.00 m
Growth Rate	Slow
Pollinators	Moths, Hand
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Yucca baccata is a plant of semi-arid regions in southwestern N. America and, although capable of withstanding occasional vey cold weather (one estimate says that it can withstand -30°c[]), it strongly dislikes moist climates, especially in winter. It is generally capable of growing outdoors in the milder regions of the temperate zone, though might require protection from winter rain. A plant at Kew Gardens, England (1992) has survived the last 3 winters outdoors[]. This plant is still thriving in 1999, though it has not grown much and has not flowered[]. Another plant is thriving in an open sunny position at Cambridge Botanical Gardens in England and must have experienced temperatures of at least -10°c, probably somewhat lower[].
Thrives in any soil but prefers a sandy loam and full exposure to the south[]. Plants are tolerant of alkaline soils[]. Plants are hardier when grown on poor sandy soils[]. Prefers a hot dry position[], disliking heavy rain[]. Established plants are very drought resistant[].
Yuccas are pollinated by small, white Yucca moths (Tegeticula yucasella and related species) with which they have a special plant-insect mutualism. At night, the fragrant flowers attract the female moth that feeds on the nectar. She then rolls pollen from the flowers into a ball that is three times the size of her head and carries the pollen ball to the next flower. There, she first lays eggs inside the immature ovary and then deposits the pollen on the flower’s stigma ensuring that seeds will form to feed her progeny. Because the larvae mature before they are able to consume all of
the seeds (60 to 80% of the seeds remain viable), the plants are able to reproduce as well[]. In regions where the moth cannot live and, if fruit and seed are required, then hand pollination is necessary[]. This can be quite easily and successfully done using something like a small paint brush.
Individual crowns are monocarpic, dying after flowering[]. However, the crown will usually produce a number of sideshoots before it dies and these will grow on to flower in later years[].
Plants in this genus are notably resistant to honey fungus[].
Members of this genus seem to be immune to the predations of rabbits[]

Edible Uses

Fully ripe fruit - raw, cooked or dried for winter use[, , , , , , ]. A staple food for several native North American tribes, the fruits are large, fleshy, sweet and palatable[, , , ]. The ovoid fruit is about 17cm long and 7cm wide[]. Considered to be a luxury by the native North Americans[], the fruits were often baked in ovens[]. The cooked fruit can be formed into cakes and then dried for later use[]. Large quantities of the fruit has caused diarrhoea in people who are not used to it[]. The dried fruit can be dissolved in water to make a drink[].

Flower buds - cooked[, , , ]. A soapy taste[]. The older flowers are best[], they are rich in sugar[]. The flowers, harvested before the summer rains (which turn them bitter), have been used as a vegetable[].

Flowering stems - cooked[]. Harvested before the flowers open then roasted[].

Seed - cooked. It can be roasted and then ground into a powder and boiled[, ]. It contains up to 30% oil and more than 10% protein, and is doubtless nutritious[]. (As Yucca arizonica)

The tender crowns of the plants have been roasted and eaten in times of food shortage[].

The young leaves have been cooked as a flavouring in soups[].

Medicinal

An infusion of the pulverized leaves has been used as an antiemetic to prevent vomiting[].
Extracts of the leaves are reported to possess anti-fungal activity.[]

The fruits have been eaten raw as a laxative[].

The roots are antiinflammatory, antitumor, antiviral[].
The roots of Yucca species are rich in saponins and medicinally active compounds. The roots, harvested when the plant is not in flower, are used to make a health-promoting drink. It has been shown to lower cholesterol and triglyceride levels in the blood, to lower blood pressure and to reduce symptoms of osteoarthritis such as pain, swelling and stiffness. Yucca schidigera seems to be the species most often quoted, though all species contain the saponins[, ].
Taken orally, the root is used in the treatment of osteoarthritis, hypertension, migraine headaches, colitis, stomach disorders, hypercholesterolemia, diabetes, poor circulation, and liver and gallbladder disorders[].
Applied topically, it is used to treat sores, skin diseases, inflammation, bleeding, sprains, broken limbs, joint pain, baldness, and dandruff[].

Many compounds from yucca have been used in the synthesis of new drugs[].

Other Uses

A tough fibre is obtained from the leaves, it is used for making ropes, baskets and mats[, , , , , , , ]. The fibre can be braided into a good quality rope[].
The leaves can be reduced into fibre and then made into cloth[]. To obtain the fibre, the terminal spine and a section of the back of the leaf are removed and pounded to free the fibre from the fleshy portion of the leaf[]. Another method of obtaining the fibre was to fold the leaves into sections about 10cm long. The leaves were then boiled with a small quantity of cedar ashes. When sufficiently cooked, the leaves were placed in a bowl or basket and cooled, then youths and young women would peel off the epidermis and chew the leaves, starting at one end and finishing at the other. After chewing the leaves, the fibres were separated, straightened out and hung to dry. When required for weaving, they would first be soaked in water to soften them[].

The whole leaf is sometimes split into sections and then tied together by square knots to make a rope[, ].
The leaf can be used as a paint brush[]. Leaf slivers are used, the end being pounded to reveal the fibres[]. The leaves have also been used to make small brushes for pottery decoration[].
The leaf is used in basket making[, ].

The leaves can be split and then woven into mats[].
The leaves can be split and used as a temporary string[]. The leaf fibre has been braided into ropes[].

Small roots have been used in making baskets[]. They have been used to produce a red pattern in baskets[].

The terminal spines on the leaves have been used as needles[].

The dried leaves have been boiled with gum, hardened, ground into a powder then mixed with water and used to make baskets waterproof[].

The roots are rich in saponins and can be used crushed and then soaked in water to release the suds for use as a soap[, , , , ]. It makes a good hair wash[, , ] and can also be used on the body and for washing clothes[]. A soap can also be obtained from the leaves and stems[].
The juice of the plant has a wide variety of uses. In agriculture it is used as a base in liquid fertilizers where its ability to reduce surface tension of irrigation water greatly assists penetration in heavy soils; it assists in soil flocculation to a marked degree; it serves as a carrying agent for the plant-food chemicals[]. The yucca extract itself is rich in the vital minor elements including boron, iron, magnesium, manganese, copper and zinc[].
The juice is said to be widely used as a carbon dioxide stabilizer in the control of oil fires, and saponin from yucca is considered a good base for soaps, shampoos, cleansing powders, and tooth pastes and powders[].

Propagation

Seed - sow spring in a greenhouse. Pre-soaking the seed for 24 hours in warm water may reduce the germination time. It usually germinates within 1 - 12 months if kept at a temperature of 20°c. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in the greenhouse or cold frame for at least their first two winters. Plant them out into their permanent positions in early summer and consider giving them some winter protection for at least their first winter outdoors - a simple pane of glass is usually sufficient[]. Seed is not produced in Britain unless the flowers are hand pollinated.
Root cuttings in late winter or early spring. Lift in mid spring and remove small buds from base of stem and rhizomes. Dip in dry wood ashes to stop any bleeding and plant in a sandy soil in pots in a greenhouse until established[].
Division of suckers in late spring[]. Larger divisions can be planted out direct into their permanent positions. We have found that it is best to pot up smaller divisions and grow them on in light shade in a greenhouse or cold frame until they are growing away well. Plant them out in the following spring.