Ecological Importance of Aloe

Aloe is a perennial liliaceous plant with succulent green leaves.

Aloe originated in Africa and has been used by humans for almost 6,000 years. It can grow in nutritionally poor soil and can also tolerate drought, making it an invaluable plant in dry regions. The plant belongs to the lily family and the genus contains over 300 different species. It is native to the Mediterranean region of southern Europe and north Africa. The genus includes small grass-like herbs a few inches tall to larger species with imposing 60-foot trunks, occupying the ecological niche of trees.

Ecological Restoration

Areas which experience prolonged drought can benefit from the planting of aloe.

In many of the semi-arid grasslands and shrub-lands that occupy 80 percent of Kenya, desertification is imminent due to overgrazing and the demands of the human inhabitants. According to the Society for Ecological Restoration International, the answer lies in the propagation and planting of native Aloe secundiflora (Liliaceae) shrubs.

Encouraging Native Species

Aloe shrubs increase the survival and growth rate of newly planted Cenchrus ciliaris grasses. This native species has already proved invaluable in saving range-land in other parts of Kenya. Aloe shrubs are also known to improve soil conditions around them and to encourage the range of other plant species in the local area.

Further Afield

The growth of aloe is viewed as a powerful way to encourage biodiversity and aid conservation in other areas. Ironically, this is often a byproduct of the poorer inhabitants' desire to make some money in the process. Across the drier parts of Africa such as the Eastern Cape in South Africa and the Karamoja in Uganda, people propagate the plant in order to tap its sap.

Dangers of Over-Exploitation

The commercial appeal of aloe often results in unsustainable harvesting practices. The threats that result from the over-exploitation of wild aloes include ecological imbalance to the area and the possible loss of the species. Thankfully, the warnings are being heeded. A Kenyan presidential decree in 1986 banned the harvesting of wild aloes.

Environmental Necessity

As well as its demonstrable efficacy in range-lands rehabilitation, the aloe plant benefits the environment in other ways. For example, the blossoms of the Aloe dichotoma (or quiver tree) draw birds and insects as well as nectar-seeking baboons. In its natural habitat it is one of the only forms of tree and can host huge colonial nests of social weaver birds.

References

• New Perspectives on Aloe: The History of Aloe
• Process Biochemistry: Physiological and Ecological Characters Studies on Aloe Vera Under Soil Salinity and Seawater Irrigation
• University of California: Facilitative Effects of Aloe Secundiflora in Degraded Kenyan Rangelands
• Kenya Wildlife Service: Strategy for Conservation and Management of Commercial Aloe Species in Kenya