Texas Mountain Laurel
Common Names: Mescal Bean
Light: Full Sun/Part Shade
Height: 10′ – 20′
Spacing/Spread: 6′ – 14′
Interest: Srping flowers, Year around evergreen foliage.
Texas Native: Yes, plant is Texas native.
Extra: WARNING, POISONOUS SEEDS. Deer Resistant.
Wildlife habitat: Provides food/shelter for bees, butterflies and birds.
Features: A wonderful Texas native tree. Thrives in Full sun/Part shade. Xeriscape plant.
Austin Native Landscaping: “If there is one Texas native, small growing, flowering tree you can’t go wrong with, it’s of course a Texas Mountain Laurel. This hard as nails, extremely drought tolerant Texas native (can survive on a partly 14 inches of annual rain) will grace any landscape with its presence. Best of all, its an evergreen! Perfect to conceal that unsightly neighbor of yours or disguise that noisy road near the window. You can train it to a tree form or leave it in a more natural shrubby form. Excellent as a specimen tree and also planted along . The showy purple blooms smell terrific; some describe it as grape soda smell, some think it smells like bubble gum or even kool-aid. The only two cons we can think of are its very slow growing pace and its poisonous seed pods. “
Family: Papilionaceae (Pronounced – pa-pil-ee-uh-NAY-see-ee)
Species: Secundiflora (Pronounced –sek-und-ee-FLOR-uh)
If you ever happen to find yourself wandering the cedar breaks of the rocky hill country between the Rio Grande and Austin, perhaps exploring one of the area’s beautiful state parks, you will undoubtedly encounter the Texas mountain laurel (Sophorasecundiflora). Distributed widely across this scenic habitat, Central and West Texas make up the northernmost reaches of this native species’ range. While normally called the Texas mountain laurel or mescal bean in English, the species’ geographic distribution actually lies mainly within the borders of Mexico where it is commonly referred to as the frijolillo for its abundant and colorful legumes which appear after the spring flowers have been pollinated. These little red beans occur in sets of six or seven and are contained in silvery seed pods covered in hairs. In contemporary Texas, many may be familiar with these seeds through the immature childhood antics associated with them. Many have both fond –and traumatizing- memories of rubbing the seeds eagerly on a bit of concrete until the friction makes them incredibly hot, after which they are placed on an unsuspecting friend’s skin to great amusement. This painful example of impulsive decision making in children and Lord of the Flies–esque behavior is actually a small part of the long story of human interaction with the species. The beans are known to be used by at least a dozen cultures throughout prehistory and the 19th and 20th centuries in Texas and Mexico. While used widely in low doses throughout the region and beyond by indigenous cultures as an intoxicant and hallucinogen during ceremonies, the alkaloid found in the bean often also causes nasty effects including respiratory depression and death if taken in higher doses. Due to the inherent danger in the use of the species as a sacrament Native American tribes throughout the United States were quick to adapt to using peyote, which has the same general distribution with the mountain laurel and is much safer.
Mountain laurel is a perennial evergreen in the family Fabaceae, and is well suited to rocky soils which receive little precipitation. Like all members of the legume producing Fabaceae family, Texas mountain laurel has a special relationship withnitrogen fixing bacteria and plays an important role in the ecosystems in which it is found. Diazotroph is the term given to describe the unique bacterial which have the ability to turn atmospheric, raw nitrogen unusable to plants species into ammonia which is ready to be absorbed by the roots and used in the production of all necessary organs. This interaction is considered “mutualistic”, one of several ecological classifications of species interaction, due to a mutual exchange of resources between the bacteria and the plant species. In return for the ammonia which it supplies, the Diazotroph (specifically called a Rhizobia in the case of Fabaceae) receives organic acids which are used as an energy source. In this way, the bacteria is able to exchange nitrogen that it “fixes” from the atmosphere which is found in soil into a usable form for the plant, increasing the overall fertility of the landscape. This is an organic fertilization method employed by many farmers throughout the world who plant legumes like alfalfa in rotation with normal crops to ensure future productivity and deter erosion. The flowers of the Texas mountain laurel are celebrated by many, as much for their abundance and delightful purple color as their amazing scent, which seems to mix the senses with a“purple” fragrance often described as grape soda or kool-aide. The large seed pods which appear shortly after the flowers are pollinated and are covered in trichomes. Trichomes are thin hair-like growths common in many species of plant and are an extension of the dermal cells found coating the outside of plant organs. Often found on leaves but not limited to any distinct part, trichomes are found in a diverse array of shapes and forms and have many functions. They often contain alkaloids and function as a chemical deterrent or toxin. Others have a physical shape which causes injury to any insect, bird and mammal which tries to eat the organ on which the trichome is located.
The association between humans and the mescal bean goes back thousands of years and has been found to be widespread throughout the species’ distribution. Often used like a bead on clothing and jewelry, archeological evidence from caves in the lower Pecos region has been discovered which shows usage of the bean as far back as 4500 BC. More sites containing the bean include dwelling and refuse excavations that have been dated to more modern prehistory. Among the numerous toxic compounds the beans contain, the alkaloid cytisine is structurally similar to nicotine and effects the same receptors. Just like nicotine, in high dosages the alkaloid is very toxic and causes nausea, vomiting headaches and death, while in lower doses cytisine produces stimulating and sensory enhancing effects. Due to the variance in alkaloid content within the species and difficulty associated with measuring dosages for oral ingestion, the bean is now generally considered a dangerous toxin. In modern pharmacology, calculated doses of the compound are marketed in Europe and have recently been undergoing testing in the US to help smoking cessation. In theory it works like methadone by binding more strongly to the nicotinic receptor than nicotine therefore giving little to no effect from smoked tobacco. In the 19th century a mescal bean society gained popularity among many Native Americans as the pioneers and immigrants arrived during Manifest Destiny and slowly suppressed their cultures. This society occasionally used the bean as an intoxicant during rituals, but also as an ornament in ceremonies. Eventually the mescal bean society was eclipsed by the modern Native American Church, which uses peyote as a safer sacrament and mescal beans only as adornment in its vision ceremonies.
Lately, Texas mountain laurel has gained immense popularity as a native landscaping stand out. This is partly because of its ability to thrive in rocky, dry soils, as well as its beautiful and fragrant blooms which adorn its delightful evergreen foliage. Once established, the plant will resist drought easily and produce pretty red beans which contain a cultural legacy important to the region and its modern inhabitants. Ecologically important, the species interacts with nitrogen fixing bacteria to permanently improve the quality of soil where it has grown or been planted. Easily trim the mountain laurel into either a shrub or small tree, and then collect the crimson beans in the shade of its thick foliage while paying homage to a species which has been a caretaker of man, as well as nature.