|Mesquite trees really do
have a good side
|January 14, 2009
Charla Borchers Leon,
|Photo Credit: Photos: Beth Ellis Victoria County Master Gardener
Young mesquite trees cut at ground surface, often result in multiple sapling regrowth that forms a thicket-type foliage with long, sharp thorns that are a nuisance to livestock and humans.
|Photo Credit: Beth Ellis VCMGA
The same young mesquite tree, when pruned, begins to take shape and form a central trunk structure
|Photo Credit: Beth Ellis/VCMGA
Excessive watering during establishment of a mesquite tree can create a shallow root system, which can cause the tree to eventually lean or heel over. While unnatural to the eye, this may be desirable to some homeowners for the interest it adds to the landscape.
|Ah, the mesquite. Ask a rancher what they think about this tree, and you might not be able to repeat the words in polite company. Townies don't rate it much higher based on the bad press this little tree receives. While it presents a challenge if it's growth habit is not understood, like most things the much maligned mesquite does have a good side - and for homeowners and cattlemen it's one well worth investigating.
The old story goes that while waiting to be driven to market, longhorns pastured in mesquite country far to the south, browsed on the beans. As the cattle were driven on the arduous journey north, they proceeded to dot trails from South Texas to Kansas with natural fertilizer loaded with untold numbers of mesquite seeds just waiting to sprout. While some elements of the story are true (and cattle do play a major part), it turns out that this old yarn doesn't tell everything.
What Mother Nature Intended
The digestive tracts of several animal species are involved in the distribution of mesquite seeds. If left undisturbed the seedlings produce a long tap root and generally one trunk. In the natural scheme of things, the trees are widely spaced, providing plenty of room for other plant species to flourish. Mesquites are nitrogen fixers, so grasses growing in their dappled shade become higher in nutritive value than grasses growing in open areas. If everything worked as it should, the mesquite would be Mother Nature's way of replenishing overgrazed, nutrient-depleted areas to the benefit of local habitat. Problems arise, however, when we humans get involved.
Past land-use practices caused overgrazing and depletion of vital soil nutrients, which acted as the first step in converting the mesquite into a pest species. These conditions killed off all but the hardiest plants, and faced with little competition, the sturdy mesquite moved in to start the habitat repair work assigned to it by Mother Nature. So far so good, but now comes the second step down the long road to Mesquite Tree Perdition. Old-time ranchers viewed trees as taking valuable water from grasses needed to feed cows. Chopping and disking worked to remove most tree species, but proved disastrous with mesquite. It turns out that mesquites, just like many of us humans, tend to respond with a touch of hysteria when their normal routine is disrupted. Chopping a mesquite to the ground causes the root bud to send up multiple saplings. Chopped roots will do the same. The end result? Where there was one tree, now there is a thicket. Herbicides and other measures don't work well, so continuing eradication efforts escalates the problem. Ultimately, the thickets choke out other vegetative species, limit habitat and grazing area, and spell physical misery in the form of wicked thorns for cowboys, horses and cattle alike.
In the Home Landscape
All this being said, mesquites are welcome additions to home xeriscapes. Simply avoid damage to the roots and prune branches to promote the structural quality of the tree. There are several types of mesquites, but in this area the honey mesquite (Prosopis glandulosa) is most common. Size is variable, but healthy mesquites can grow up to 30 feet in height and spread. They are not choosy about soil and don't need fertilizing; in fact, the only thing they dislike is too much water. They'll definitely take it if offered, but just like a person eating too much junk food, it negatively affects the health of the tree by promoting pests and making the tree top-heavy.
Establishment of Healthy Trees
Obtaining new trees is easy. Scarify and soak seeds in water for 24 hours before planting, start root cuttings or transplant young trees from the wild. Avoid over-watering during establishment because this creates a shallow root system, which can cause the tree to eventually lean or heel over (although this may be desirable to some homeowners for the interest it adds to the landscape). Avoid pot-bound container plants because they will never develop a proper tap root. Healthy, young mesquites grow quickly, losing most of their thorns as they mature.
A healthy mesquite is a structural beauty. The lacey leaf structure provides dappled shade and the gnarled bark provides both visual interest to humans and cozy habitat for lizards and other small creatures. Bent or twisted trunks are quite striking in appearance. Leaf color provides an interesting counterpoint to other vegetation.
The tiny spring blooms (which form clusters called catkins) are pretty and lightly fragrant. Beans add yet more structural interest and add a nice touch of reddish color in autumn. Mesquites are excellent wildlife trees, providing food, nectar, pollen, shelter and nesting spots for a variety of animals and birds.
Texas Tough and Beautiful to Boot
Consider adding a mesquite to your landscape or clean up the ones you already have. Avoid injuring the roots, water sparingly, and prune to enhance the open structure of the tree. Respect its growth habit, and you will end up with a tree that's Texas Tough and beautiful to boot.
|LEARN MORE ABOUT THE MESQUITE TREE
Or read up in these publications:
Simpson, Benny J.
1988 A Field Guide to Texas Trees. Gulf Publishing Company.
Taylor, Richard B, Jimmy Rutledge, Joe G. Herrera
1997 A Field Guide to Common South Texas Shrubs. Texas Parks & Wildlife.
Vines, Robert A.
1990 Trees, Shrubs, and Woody Vines of the Southwest. Texas Press.