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 Senegalia[].

Common Name: Catclaw Acacia

General Information

Senegalia greggii is a heavily armed, deciduous shrub or small tree growing from 1 - 9 metres tall[]. In favoured sites the tree can reach 11 metres, with a trunk up to 30cm in diameter[].
The plant is used traditionally as a food, medicine and source of materials. It produces a good quality wood that is used for cabinet work, craft items etc. The plant is of high value in land restoration projects.

Known Hazards

Plant parts contain prunasin, a poisonous cyanogenic glycoside[]..

Botanical References

Range

Southwestern N. America - California, Nevada, Utah, Arizona, New Mexico, Texas, south to northern Mexico

Habitat

Dry gravelly mesas, canyons, arroyo banks, rocky hillsides, desert flats, washes, floodplains, and riparian areas[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	6.00 m
Growth Rate	Medium
Pollinators	Insects
Cultivation Status	Cultivated, Wild

Cultivation Details

Senegalia greggii is a plant of arid and semi-arid regions of southwestern N. America, where it is found at elevations up to 1,800 metres. It grows in areas where summers can vary from warm to hot with highs ranging fom 21 - 49°c and winter temperatures can fall as low as -10°c in some areas whilst in others they do not go below zero. Rainfall can vary from as little as 65mm a year in the most arid regions up to 500mm[].
The plant requires a sunny position in a well-drained soil. The desert soils typical of catclaw acacia habitat are low in organic matter, can be slightly acidic to slightly alkaline, are often shallow (less than 30.5cm) deep), and commonly contain calcium carbonate in the upper 2 metres of soil. The caliche layer can be thick and impenetrable[].
Although it is usually top-killed, the plant generally resprouts very freely following a fire[].
Catclaw acacia is highly adapted to harsh desert conditions. A deep root system, high water use efficiency, high photosynthetic capacity, and use of the C3 photosynthetic pathway allow catclaw acacia to thrive in harsh desert climates. Catclaw acacia roots greater than 5.5 metres deep have been recorded in southeastern Arizona. On a wash site in the Gold Valley of the Mohave Desert, 55% of the total catclaw acacia dry weight was root[].
Plants are known to live for at least 120 years[].
Although many species within the family Fabaceae have a symbiotic relationship with soil bacteria, this species is said to be devoid of such a relationship and therefore does not fix atmospheric nitrogen[].

Edible Uses

Seed and seedpods - fresh, dried, or ground into powder[]. A bitter flavour, they are generally only eaten when better foods are not available[, ]. The pods were eaten[]. The seeds are round and typically 5 - 7mm in size[]

Medicinal

The pods are used to make an eyewash to treat conjunctivitis[].

The leaves and pods, when ground into powder, will stop small amounts of bleeding and soothe chafed skin or diaper rash. When this powder is made into a tea, it can be used as an antimicrobial wash or drunk to treat diarrhea and dysentery. Native Americans used catclaw acacia to soothe sore flank and back muscles of their horses[].

The flowers and leaves in tea can treat nausea, vomiting, and hangovers[].

The thick, sticky catclaw acacia root, when made into tea, treats sore throats, mouth inflammations, and coughs[].

Agroforestry Uses:

Catclaw acacia is a valuable plant for use in restoration projects in sites such as asbestos and mining waste, and other disturbed sites. It is usually planted as young trees, but is also sometimes used in seed mixes. By using tillage, mulch, and site-adapted seed along a pipeline corridor in Arizona, the revegetated site closely resembled nearby undisturbed sites just 10 years after planting[]. Transplants were 100% successful on an abandoned asbestos milling site, even though there was considerable rodent herbivory in the area[]. Seedlings also survived on a gold mine spoils site in the Mohave Desert. Survival rates were not reported[]. Catclaw acacia was one of many species used to revegetate disturbed sites (road side cuts, mining sites, eroded hillsides, and gullies) by the Utah Division of Wildlife Resources and other cooperators. In southern desert shrubland areas, catclaw acacia established well when transplanted, spread well by seed, and survived on alkaline or acidic soils. In categories of natural vegetative spread, growth rate, soil stability, and disturbance tolerance, catclaw acacia received mid level ratings[].

Other Uses

The wood is strong, hard, tight grained, and heavy. It is used for cabinets, turnery, and fencing. The contrasting reddish brown heart wood and yellow sapwood makes it valuable for making souvenirs[].
The wood has been used as a fuel[].

Propagation

Seed - best sown as soon as it is ripe in a sunny position in a warm greenhouse[].The dried seed of most, if not all, members of this genus has a hard seedcoat and may benefit from scarification before sowing to speed up germination. This can usually be done by pouring a small amount of nearly boiling water on the seeds (being careful not to cook them!) and then soaking them for 12 - 24 hours in warm water. By this time they should have imbibed moisture and swollen - if they have not, then carefully make a nick in the seedcoat (being careful not to damage the embryo) and soak for a further 12 hours before sowing. Sow the seed in Spring in a greenhouse. 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.
Acacia seeds that have matured fully on the bush and have been properly dried have a hard seed coat and can be stored in closed containers without deterioration for 5 - 10 years or more in dry conditions at ambient temperatures. It is best to remove the aril, which attracts weevils and can lead to moulds forming. The arils are easilyremoved by placing the seeds in water and rubbing them between the hands, then drying the seeds and winnowing them[].
When growing catclaw acacia seed in containers, a tall container is recommended to house the rapidly developing root system[]. The root length of catclaw acacia seedlings was greater than 60cm 4 - 5 months after planting on watered sites[].