Mesquite trees belong to Arizona. As the editor and author of the website Jay Sharp DesertUSA.comSaid, “Mesquite bushes symbolize our southwest desert”, as much as “coyote, black-tailed male rabbit, western diamondback rattlesnake, scorpion, cactus and prickly pear cactus”. Indeed, the mesquite trees in Arizona “mixed into the life of the land like cornbread and tortillas.” (Lometa)
Perfectly adapted to the desert
Mesquite plants are very hardy desert trees that have adapted to life in the desert landscape of Arizona and surrounding areas over the past few centuries. All their physical properties ensure their survival here, including leaves, pods and roots. They grow well in full sun and high temperatures, but they can also tolerate the cold in Arizona’s winter (down to 0 degrees Fahrenheit). Sometimes they are found at higher altitudes and can adapt to shallow rocky soils. According to reports from the United States Department of Agriculture and Forest Service, mesquite trees can live for more than two centuries. (sharp)
Mesquite trees in Arizona can survive in areas where the root system is swollen and there is little rainfall. The lateral roots of the mesquite tree protrude many times beyond the canopy. They also have deep roots and can dig up beverages 175 feet below the ground, although the more typical depth is 50 feet. Therefore, they can get water at the top and bottom layers of the soil at the same time.
The tiny waxy leaflets of the mesquite tree retain precious water by minimizing water loss due to transpiration. They are deciduous trees, which means that they provide excellent shade in summer, but they will drop their leaves and provide warmth with sunlight in winter. During extreme droughts, they drop their leaves prematurely, which further reduces transpiration.
Mesquite trees are members of the legume family (a relative of beans and peas), which makes them particularly suitable for arid environments. Mesquite trees have the ability to fertilize themselves and surrounding plants through a symbiotic relationship with soil bacterial colonies. Bacteria living on the roots of mesquite shrubs transform or “fix” nitrogen in the atmosphere, thereby providing minerals in the soil that are essential for plant growth and germination. Many gardeners use the same process to increase soil fertility by planting nitrogen-fixing cover crops. (Sharp, Sharp)
The mesquite trees in Arizona are surprisingly prolific. Their beans are packed in protective pods, which are very durable. In fact, “seeds can survive undisturbed in the pod for up to 40 years.” (Clayton) Animals play an important role in the thinning of seeds (required for germination) and spreading through feces.
The mesquite tree is easy to identify and looks almost like a giant fern bush. They can reach a height of 30 feet, but the common mesquite trees that grow in the Arizona desert are only about half of this kind of tree. Many have multiple trunks. Under the worst conditions, mesquite bushes are more like bushes than trees. Their branch structure is usually very twisted and joined, which adds to their uniqueness. In spring and early summer, they show clusters of finger-like protrusions covered with delicate flowers. Subsequently, long and thin pods are formed, which are usually brown but have different appearances between species. Many types of mesquite trees have some type of thorns. They may be short or scary (and they are all very sharp!).
Three Arizona mesquite tree natives and their cousins
There are about 40 varieties of mesquite in the world, but there are three in Arizona. They not only grow in the Sonoran Desert, but also in the Mojave and Chihuahua Deserts. Their range is staggering, spanning tens of millions of acres from western Texas to California, from Mexico to southern Utah. Within the above range, they can thrive in a variety of habitats. (Lometa, Sharp)
The three native mesquite species in Arizona are:
- Gland -Known as Honey Mesquite or Texas Mesquite. These usually have a crying form and can be quite beautiful.
- squid -Known as the Arizona Mesquite or Native Mesquite. It is also called velvet legume because the soft hair covers the young growth. They are quite fluffy and roar in appearance. They are popular in nurseries and grow well on lawns and golf courses.
- Pubic bone -Known as Spiral Beans, mesquite shrubs are named for the spiral or coiled shape of their seed pods.
In addition to these three, Arizona has also planted many other types of mesquite trees. Many are hybrids of honey, velvet or screw bean shrubs, mostly occurring where the respective ranges of these natural species overlap. Others are non-native legume shrub species, most of which originated in South America. There are Argentine legumes (Prosopis alba), Chilean legumes (Prosopis chilensis) and many other varieties and their hybrids. No exotic species is more suitable for the climate here than the mesquite bushes in Arizona. For example, Chilean mesquite species seem to be unable to tolerate the lower winter temperatures in Arizona.
Although the mesquite tree has many positive qualities, many people still regard it as an invasive weed. They are extremely aggressive and troublesome in many countries outside North and South America that have introduced them, especially in Australia.
Mesquite trees are also cursed by our own Arizona desert residents. Herders especially dislike them, but over the past two centuries, the overgrazing of cattle has exacerbated their complaint, namely the competition between mesquite trees and grass. In this overgrazing area, cattle not only threaten the natural grass population that competes with mesquite trees for water, but also help mesquite spread by eating and dispersing seeds. As Frank Dobie said: “The white man is sowing in overgrazing land; he is now harvesting legume bushes that have stabbed millions of acres of land and made them unable to produce.” All efforts to control this native Arizona tree have failed and are considered impractical or ineffective. Whether it is through fire, the use of herbicides, or physical tree removal through various methods, the cost and environmental side effects of trying to control the population and spread of legume bushes have made this problem difficult to solve.
Sharp reminds us: “Uninvited guests or welcome neighbors, mesquite belong to the desert. They evolve in the desert. They play a central role in the desert ecosystem.” (Jay Sharp)
Historical significance and modern use
“In the past few centuries, no plant has played a greater and more important role in human life in the southwestern United States than the dwarf, curved mesquite.” (Excerpt from Magnificent Mesquite Indeed, the mesquite trees scattered in the southwest have actually saved countless lives. They provided the victims of the 1841 Texas Santa Fe expedition with “nectar from the sky”, as recorded in George W. Kendall’s diary (quoted by Rogers). Beans are sweet and nutritious, and richer in protein than soybeans. (Lometa)
Another food (though not directly) from mesquite trees in Arizona is honey. After all, bees that attract nectar from mesquite flowers in groups not only play an important role as a pollinator. However, this is not a complete list of foods derived from legumes. Their juice is even used as sweet gum or black dye.
“Pinole” is made by grinding pods with or without beans. Because of its sweetness, it can be used as four, and can also be used as a condiment or spice. It is said that this legume flour is healthy for diabetics because it is sweetened by fructose, which can be processed in the human body without insulin. This is just one example of the many digestive and nutritional advantages of mesquite trees and other foods in the desert. (Lometa)
The various parts of the Mesquite tree were also used by the Indians and settlers of the Frontier era as a remedy for many different diseases. Mesquite trees relieve or cure diseases including: diarrhea, dysentery, colic, meat injury, headache, eye discomfort and sore throat.
The wood, bark and pods of mesquite trees are commonly used for barbecues and other purposes. Dry wood burns slowly, is hot and has almost no smoke. It has a distinct aroma. Some people insist that burning the pods with charcoal and wood chips will make the flavor stronger. (Lometa) In addition to heating and cooking, it is also used to build Spanish missions, colonial manors, pastures and fences. The (sharp) American Indians used hard mesquite wood to make spears and arrows, and mesquite bark to make baskets and fabrics. The thorn is used as a needle. Nowadays, wood has artistic value in the manufacture of furniture or sculptures due to sometimes dark and beautiful rough patterns.
Of course, the mesquite trees in Arizona are not only good for humans, but also for our wildlife. Animals use mesquite shrubs as shelter, habitat and food. In late summer and autumn, mesquite beans make up as much as 80% of the coyote’s diet! When grass is insufficient, the pods can also be used as feed for livestock.
Maintenance, problems and solutions
Although the mesquite trees in Arizona do not require much maintenance, specimens growing around our houses may benefit from some extra care during unusually hot summers or during long periods of drought. Sun exposure is one of the few issues that plague mesquite trees grown as part of landscaping, although they are not as susceptible to this effect as citrus and other fruit trees in Arizona. Watering occasionally but infrequently and fertilizing occasionally will help ensure that the mesquite bushes in the home do not suffer from a decline in health and beauty.
During the rainy years in Arizona, the mesquite trees do not require additional watering. However, during dry periods, the leaves become sparse and allow more direct sunlight to hit the branches. As the city needs to evacuate mesquite trees to withstand storms and high winds, so as not to cause damage to houses and other buildings, this makes the situation worse. If the bark is exposed to strong sunlight, scorching may occur, especially in the most direct sunlight (that is, on top of horizontal branches at noon). Sun burns can cause permanent damage to the cambium or the sapwood layer under the bark. Intense sun burns can cause ruptured bark and dead tissues to cause secondary infections and infestations, such as bark beetles and a fungus called “black smoke”.
On mesquite trees in Arizona, sun burns are preventable, but unavoidable. The reflective paint on the most vulnerable branches will minimize the chance of sun damage to the mesquite tree. Branches that have been affected should be moved back to branches with healthy tissues. The best way to prevent the sun is to encourage the growth of green leaves by watering and fertilizing during the hottest time of the year to protect the trees. Give mesquite ammonium sulphate once in spring. Unless they have been fed by a dripper or sprinkler (whether in your own area or in a nearby yard), water them deeply every two months from early spring to early fall. If the monsoon brings enough water, skip deep water irrigation during this period.
Mesquite trees planted in someone’s yard may not be as strong as volunteer trees that are wild in the desert. Most likely, the nursery mesquite trees planted for landscaping purposes have been spent in pots for some time. The longer any tree spends in the pot, the more likely it is to become a root system. The damaged root system can lead to a mesquite tree that not only has difficulty getting the small amount of water it needs, but it also falls more easily because its “anchor” is not so strong. John Begeman said: “As far as you can, it is impossible to anchor a swaying tree to the ground.