In an ambitious move to eradicate an invasive cactus plant, Laikipia North residents are converting it into biogas.

For decades, cactus plants have colonised hundreds of thousands of acres of land in the pastoral areas, limiting grazing fields and resulting in death of livestock when consumed due to their thorny nature.

“The invasive opuntia stricta spreads very fast on our land and homesteads, forcing some families to abandon their homes. It’s a destructive plant, mostly affecting sheep because it makes it difficult for sheep to graze,” James Masaine, a resident, says.

The cactus that was introduced to Kenya by colonial administration has been blamed for causing deaths to livestock that feed on its brightly purple-coloured fruit with tiny spines that cause injuries on the animals’ digestive system.

To remove the invasive species and save their land from the weed invasion residents use mechanical and chemical methods to suppress the plant with minimal success. However, a project supported by the Jomo Kenyatta University of Agriculture and Technology (JKUAT) is providing double benefits to the locals – minimising the spread of the succulent weed and utilising it in generation of clean energy by using simple technology.

Prof Willis Owino explains that JKUAT started the initiative of eradicating the cactus weed with a pilot project of two households two years ago in Makurian location in Maiyanat Community Land, which has expanded to 30 households – a move that has led them to minimising usage of wood fuel as a source of energy.

“The cactus species we have in Kenya is invasive and this forced us to look for a solution to address the challenges associated with this plant in Laikipia. Women informed us that fuel was a major setback in the region, hence piloting a biogas project in two households to see how it would perform before rolling it out to other areas,” Prof Owino says.

Sayanat Kuraru is grateful that the project now assures her of efficient cooking devoid of adverse health effects associated with wood fuel that emits a lot of smoke and also walking long distances to fetch firewood.

“We were walking long distances to fetch firewood. We have now benefitted from biogas; there is a big change compared to using wood fuel and biogas on health and cooking efficiency. Wood fuel produces soot that affects our eyes,” she notes.

The semi-arid area has in recent years lost dozens of trees felled for firewood and charcoal and as a source of fodder during drought.

Prof Owino observes that in case the invasive cactus is eradicated, introduction of spineless cactus would be ideal in future.

Research findings by Chuka University in 2020 titled Cactus invasion: A Threat to Biodiversity and Food Security shows that invasive cactus occupies 17,000 acres of land in Naibunga conservancy in Laikipia and invades at least two kilometres square per year.

• A Tell Media / KNA report / By Muturi Mwangi