Classification of the genus Acacia (in the wider sense) has been subject to considerable debate. It is generally agreed that there are valid reasons for breaking it up into several distinct genera, but there has been disagreement over the way this should be done. As of 2017, it is widely (but not completely) accepted that the section that includes the majority of the Australian species should retain the name Acacia, whilst other sections of the genus should be transferred to other genera. This species is transferred to Vachellia[].

Common Name: Mescat Acacia

General Information

Vachellia constricta is a thorny tree that can grow up to 6 metres tall[].
The plant is harvested from the wild for local use as a food.

Known Hazards

None known

Botanical References

Range

Southwestern N. Aserica - Arizona, New Mexico, Texas, south through Mexico to Oaxaca, Puebla, Queretaro, Veracruz

Habitat

Desert scrub, desert grassland, and desert riparian communities, commonly found on dry hills, mesas, slopes, canyons, and intermittently wet washes, floodplains, and drainages[]

Properties

Edibility Rating
Medicinal Rating
Habit	Tree
Height	5.00 m
Growth Rate	Slow
Pollinators	Bees, Insects, Self
Self-fertile	Yes
Cultivation Status	Wild

Cultivation Details

Vachellia constricta is a plant of arid and semi-arid regions of southwestern N. America at elevations up to 2,000 metres. It can experience summer temperatures as high as 43°c with winter lows falling to -12°c. Annual precipiation can range from 90 - 500mm, most of it falling in intense (summer) or more moderate (winter) storms[].
Requires a sunny position in a well-drained soil. Sandy to loamy soils are most often described in association with whitethorn acacia. An impervious caliche or lime layer is also commonly associated with most of these soils. Whitethorn acacia was found on soils with 6.3% to 10.9% moisture content during the period of most intense drought conditions, and dominated where the moisture content was 6.3%. Soil moisture, nitrate, ammonium, and phosphorus concentrations are higher when shrubs have ant nests beneath their canopies[].
Following top-kill, this species sprouts from the root crown[]
A fairly long-lived tree that can live more than 70 years[].
Flowers are short lived, and bees only pollinate flowers on the day flower buds open[].
This species has a symbiotic relationship with certain soil bacteria; these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[].

Edible Uses

Native Americans of Arizona and New Mexico used whitethorn acacia fruits to make pinole[]. The seeds average about 3mm wide, 5 - 6mm long, and weigh an average of 19.1g[].

Medicinal

Seri Native Americans of Sonora, Mexico, used the seeds and leaves of whitethorn acacia, pulverized and heated in water, to treat stomach aches and diarrhea. When ground into a powder, the leaves and pods can stop bleeding, relieve diaper rashes and chafed skin, and may be used as an antimicrobial wash. A similar powder has been used by Native Americans to soothe aching back muscles of people and flank muscles of horses[].

A tea from the flowers and leaves has sedative properties and eases hangovers[].

The root, when made into a tea, treats sore throats, coughing, and mouth inflammations[].

Agroforestry Uses:

Whitethorn acacia protects newly revegetated areas from grazing. It also provides erosion control and tolerates saline soils. Revegetation of a pipeline corridor in Arizona in 1986, using whitethorn acacia among several other native species, successfully resembled undisturbed sites after 10 years. Whitethorn acacia's success in revegetation of mine reclamation sites depended on the protection of the revegetated sites. Whitethorn acacia seedlings suffered 100% mortality on the revegetated exposed east slopes of copper mine waste areas of Tucson, Arizona. On the more protected north slopes, some seedlings survived for at least 7 years following the initial seeding. However, actual survival rates were unclear[].

Other Uses

None known

Propagation

Seed - best sown as soon as it is ripe in a sunny position in a warm greenhouse[]. Stored seed should be scarified, pre-soaked for 12 hours in warm water and then sown in a warm greenhouse in early spring. The seed germinates in 3 - 4 weeks at 25°c[]. As soon as the seedlings are large enough to handle, prick them out into individual pots and grow them on in a sunny position in the greenhouse for their first winter. Plant them out in late spring or early summer, after the last expected frosts, and consider giving them some protection from the cold for their first winter outdoors.
Cuttings of half-ripe wood with a heel, mid summer in individual pots in a frame[]. Overwinter in a greenhouse for the first winter and plant out in their permanent positions in late spring or early summer. Fair percentage[].