Acacia is a wide genus of plants that thrive in arid, desert climates. There are believed to be nearly 1,000 different species, ranging from tall shrubs to large trees. Acacias grow prominently in Africa and Australia, but have presences in parts of Europe and North and South America as well. Most species are edible, either by humans or herbivorous animals. The plant’s bark is also used as a medicinal compound by many cultures, and the wood of many of the larger trees is prized for its durability and weather resistance.
In general, the best known types of acacias are trees, and are often associated with either the African savanna or the Australian bush. These trees are distinguished by their long, slender trunks and their horizontal canopy leaves. The genus is much larger than just these common examples, however. A wide array of bushes, shrubs, and shorter trees are also included. All have similar bark, wood, and leaf composition, though their habitat and uses are generally quite diverse.
Acacia trees and shrubs are deciduous, which means that they lose their leaves each autumn. The plants act as natural fertilizers, as the earth around and under their canopy is often rich in nitrogen and other nutrients from decomposing leaves. In desert climates where soil quality is generally poor, acacias are often described as oases of life and greenery. Plants can often thrive on the land around an acacia when elsewhere they would perish.
Farming communities in parts of Africa selectively plant and breed acacia trees as a means of raising their crop yields. Grains, corn, and vegetables planted beneath the canopy of cultivated acacias will often flourish. This can be a godsend for communities that rarely see rain and must deal with dry, often hostile growing conditions.
Planting acacias can also sometimes be an aesthetic decision, particularly in more temperate zones. Different species have different colored blooms and are often quite attractive. Small versions are often intentionally cultivated in corporate office parks, open public spaces, and even home landscaping. So long as the trees have a wide enough space to grow and extend their roots, they will normally thrive largely on their own. Caring for acacias is usually very simple, often involving no effort once the plants are established.
Most acacia varieties, whether bush or tree, are known for the tough spines along their trunk and branches. Botanist believe that these are an evolutionary defense mechanism against animal destruction. This is not to say that acacias resist animals — indeed, most have symbiotic relationships with a host of creatures. Animals eat the leaves, seek shelter in the dense bark, and chew on bits of branches and wood. Nearly all give something back, though, which enables to plant to continue providing.
Humans are some of the plant’s only predators. Acacia wood is prized in many markets for its durability, natural shine, and general weather resistance. Most harvests are from the wild, as growing acacias commercially is relatively rare. This is not always as detrimental as it sounds, however. In a number of temperate zones, acacias spread much faster than they can be chopped down and are held by many to be something of an invasive species.
Acacia bark is also sometimes harvested for use in pharmaceuticals and natural medicine. The bark has long been used in traditional medicines. It is brewed as a tea or ground into a fibrous powder, then dispensed for ailments as wide ranging as upper respiratory problems, hemorrhages, and smallpox. Some cultures believe that the bark has supernatural powers and will wear it as an amulet or smoke it during certain rituals or celebrations.