Invasive Prosopis Juliflora

Seventy-five percent of Kenya is considered arid or semi-arid. Prosopis juliflora, known commonly as mesquite or honey mesquite, is native to Northern Mexico and the Southern United States and is highly tolerant of arid regions and droughts, growing in areas with as little as 50 mm of rainfall a year. The plant fixes its own nitrogen, can grow in nutrient-poor soils, and does not require fertilization. Additionally, this species does not require seeding and re-sprouts soon after harvest. While the tree is a short, thorny shrub, the root system is extensive and allows these trees to access both surface and deep water sources. The roots also act to store energy, and once a tree is cut down the water stored in roots serves as a water source for growing shoots.

Today mesquite, known as mathenge in Kenya, is a highly invasive pest. In the 1970s and 1980s the government paid individuals to plant the species to reduce desertification and soil erosion. However, years later mesquite is causing harm to the Garissa, Wajir, Mandera, Baringo, Turkana, Taita Taveta and Tana River communities by affecting their grazing animals and agriculture. The thorns on the bushes are poisonous to goats and other livestock. The seeds, considered sweet, get stuck in the animals’ teeth, eventually leading to tooth decay rendering the animals incapable of grazing. Additionally pastoralists have commented that the thick bush is a hiding place for wild animals or people who may seek to steal animals. Additionally mesquite displaces native plants and wildlife, and has a negative impact on underground water resources.

Prosopis Juliflora, Invasive in India too!

The World Agroforestry Centre has recommended useful products can be made from the harvest of mesquite, including fuel. We want to use mesquite to meet the energy and cooking fuel needs for those in Kenya. With a specific gravity 0.70 or higher, the wood burns slowly, evenly, and burns very hot. Currently mesquite has invaded an estimated 125, 000 acres in Kenya and has the ability to double its range every 5 years. An average tree has about 100 pounds of wood. Thus, an estimated 300 trees per acre would produce about 30,000 pounds per acre, enough to fuel 30,000 families for a day.

We are excited about the environmental and social impacts of reducing mesquite in rural communities in Kenya while giving rural and urban families a cleaner and cheaper source of fuel for their cooking needs.