''Acaciella angustissima'' (prairie acacia, white ball acacia, ocpatl, or palo de pulque) is most recognized for its drought tolerance and its ability to be used as a green manure and ground covering. It is a perennial, deciduous, and belongs to the family Fabaceae (beans/legumes) and as it grows it starts as a shrub but eventually matures to a small

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

. The tree has a high density of leaves along with small clumps of white flowers and creates 4–7 cm long seed pods. ''Acaciella angustissima'' is found in tropical areas around the equator since, its water needs can vary from 750 to 2,500 mm a year. It has an advantage it can withstand a moderate drought, since its leaves are retained even in long dry periods. Aside from being drought tolerant, ''Acaciella angustissima'' also has the benefit of being a green manure, since it has such a high leaf density, but also loses the majority of its leaves each season. So the leaves can be used in composting or can be saved and used as livestock feed. It should only be used as an additive to the feed and not the main source, since it also toxic in high doses.

Description

''Acaciella angustissima'' is normally a shrub but can also look like a small tree when fully grown, since its height can vary from 2–7 m depending on the growing conditions. Large clumps of small white flowers cover the branches of the bush. The flowers have 5 petals with a large number of stamens extended far past the petals.Tropical Forages
''Acaciella angustissima'' (as ''Acacia angustissima'')
, ''Tropical Forages'' The plant also produces a small seedpod that starts out green, but then turns brown when fully matured. The seedpods usually have a length of 4–7 cm, and are 6–8 mm wide. The leaves which are one of the plant's key traits are made up of 10–20 pairs of long thin leaves that go down a stem. They come in pairs of 3–12. One unique feature of the ''Acaciella angustissima'' is that it is thornless unlike most members of the genus '' Acacia''Texas Wildlife Center
''Acaciella angustissima'' (as ''Acacia angustissima'')
''Wildlife Center'' (which it formerly belonged to).

History

''Acaciella angustissima'' comes from the plant family Fabaceae. It only grows in very wet parts of the world, usually around the equator due to its large consumption of water. It is native to southern parts of North America, the Caribbean and the majority of South America. However, it is able to grow at almost any elevation and usually prefers a warm climate of 25–30 degrees Celsius. ''Acaciella angustissima'' is still one of the many crops under-utilized and researched. Luckily there is hope, roughly 20 years ago researches started evaluating it in tropical areas such as Zimbabwe.

Natural habitat

Altitude: 0-2600m
Annual temperature mean: 5–30 deg. C.
Annual rainfall mean: 895-2870mm
Soil: ''A. angustissima'' is well-suited for acidic, low-nutrient soils and it has very good resistance to

drought A drought is defined as drier than normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, an ...

.World Agroforestry Centre

Growing conditions

Since ''Acaciella angustissima'' is a shrub, it propagates (spreads) through its seeds or clippings. The seeds come from all the pods that the ''Acaciella angustissima'' grows each year, and the clippings should be taken from a somewhat hard branch, to better support themselves when transplanted. ''Acaciella angustissima'' should be planted in March or April in soil that has good drainage and is more on the acidic side on the pH scale. To be most effectively utilized it should be used to prevent erosion, since it has such a large root system. This is also one of its downfalls, since when it is intercropped with other species its roots can be a major competitor for vital nutrients. Luckily its fallen leaves can provide enough N, K, and P to keep smaller nearby plants healthy, and provide some shade at the same time.James E. Smith
Prairie ''Acacia''
''USDA'' ''Acaciella angustissima'' is self-sustaining and does not need fertilizer, but has been found to respond well to fertilizer when added. However, the plant has a large water requirement. It requires a minimum "rain fall" of 700 mm but can handle up to a maximum of 3 000 mm.

Uses

Alcoholic beverages

The bark is used in the production of alcoholic beverages. The root is used in the drink

pulque Pulque (; nci, metoctli), or octli, is an alcoholic beverage made from the fermented sap of the maguey (agave) plant. It is traditional in central Mexico, where it has been produced for millennia. It has the color of milk, a rather viscous c ...

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

Forage

The seeds of ''Acaciella angustissima'' are high in

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

and are somewhat useful as

forage Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used ...

for

livestock Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animal ...

.''Acaciella angustissima'' (as ''Acacia angustissima'')
/ref> The tree has a

tannin Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including amino acids and alkaloids. The term ''tannin'' (from Anglo-Norman ''tanner'' ...

content of 6%, which inhibits the ability of livestock to make use of the tree's

Medicine

The indigenous

Tzotzil The Tzotzil are an indigenous Maya people of the central Chiapas highlands in southern Mexico. As cited by Alfredo López Austin (1997), p. 133, 148 and following. As of 2000, they numbered about 298,000. The municipalities with the largest Tzo ...

and Tzeltal

Maya people The Maya peoples () are an ethnolinguistic group of Indigenous peoples of the Americas, indigenous peoples of Mesoamerica. The ancient Maya civilization was formed by members of this group, and today's Maya are generally descended from people ...

of Mexico use ''A. angustissima'' to treat

digestive tract The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans and ...

problems. They also use it to treat

toothache Toothache, also known as dental pain,Segen JC. (2002). ''McGraw-Hill Concise Dictionary of Modern Medicine''. The McGraw-Hill Companies. is pain in the teeth or their supporting structures, caused by dental diseases or pain referred to the t ...

rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are invol ...

and cuts of the

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different de ...

. Experiments have shown that ''A. angustissima'' mildly inhibits the growth of ''

Escherichia coli ''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Esc ...

'' and '' Staphylococcus aureus''.

Constraints to wider adoption

There are unfortunately many constraints holding ''Acaciella angustissima'' back from being adopted. Firstly the amount of water it needs to survive is 3 – 4 times the amount of rainfall found in more northern parts of Africa. This is unfortunate since dry land farmers could benefit the most from this tree. The second and most important constraint is that, ''Acaciella angustissima'' can actually act as a weed. It is so effective at propagation that it spreads rapidly. Thirdly, ''Acaciella angustissima'' contains roughly 10% tannins, which is the plant's natural defense mechanism. The taste created by the tannins is not usually welcomed, and the compound itself negatively affects livestock digestive systems.Anteonello Cannas
“Plants Poisonous to Livestock
''Cornell University – Animal Science''

Practical information

The most important fact about ''Acaciella angustissima'' is that it has turned into a weed in its native habitat, so it should only be used in a controlled environment or when absolutely necessary. The only times it should be considered are when dealing with a harsh conditions where only weeds can survive, and some type of ground cover is needed to help with erosion control. If these circumstances are true, then the expected final height of the plant should be kept in mind when planting to prevent over crowding. Intercropping would also be complementary, by allowing farmers to take advantage of the unused space between plants, the nitrogen fixing habit, and the shade provided by the bushy branches. Due to the complex structure of the leaves it can take a year for them to decompose and release nutrients into the soil. To create a seed bank, it is important to remove all the seeds from the pod, and then clean them before storing, so that the pod doesn't break down and start attracting insects.

References

External links

The Nature Conservancy

''Acacia angustissima'' (www.fieldmuseum.org)
{{Taxonbar, from=Q521478 angustissima Shrubs Forages Flora of India (region) Flora of South America Entheogens