What you need to know:
- An invasive species of cactus plant has remained a thorn in the flesh to pastoral communities in Laikipia County for over a decade.
- At Twala Cultural Manyatta, a group of women have come up with a biogas production utility that utilizes biomas from the succulent cactus leaves, to produce clean cooking gas.
For more than a decade now, an invasive species of cactus plant has remained a thorn in the flesh to pastoral communities in Laikipia County.
It has colonized tens of acres of the community grazing land, suppressing pasture growth in the process. Worse still, it has caused deaths of livestock by inflicting septic wounds in their mouths as a result of consuming the plant's prickly purplish fruit.
Methods employed in the recent past, towards reducing the spread of this species of the cactus - Opuntia Stricta include physical removal, utilisation as a source of clean energy, and biological (use of predatory beetles that feed on the succulent leaves).
Little progress has been witnessed so far. As a result, a group of women from Laikipia North Sub-county, one of the worst affected areas, have decided to give one final push, which they believe will be fruitful; if only they get support from government and development partners.
They have set up a demo farm, near Il Polei Shopping Centre where they say they have eradicated 95 per cent of the invasive plant in their 40-acre piece of land.
At Twala Cultural Manyatta, the 203 women have come up with a biogas production utility. It utilizes biomas from the succulent cactus leaves, to produce clean cooking gas. They have also set up a greenhouse for breeding the cochineal insects and another greenhouse farm planted with various crops.
“The three projects are intertwined. The waste from the biogas digester is utilized as manure, all in an effort to reap the benefits of the invasive plant even as we work towards eliminating it completely. The predatory beetles we breed here is a supplement to this goal,” explains Rosemary Nenini, the manager at the cultural centre.
Ms Nenini says the centre was established in 2009, and brings together six women groups who engage in various income generating activities among them ecotourism. They have also put up accommodation facilities for tourists. By using biogas for cooking, they reduce cost of energy while solving a societal problem.
“Being part of the wider community, we take pride in taking part in providing solutions to one of the persistent environmental problems. Our biogas project, which some of the group members have adopted in their individual homesteads, will go a long way in providing a home-based solution on the cactus eradication initiative,” says Ms Nenini.
The process of biogas production involves grinding the cactus leaves into thick pulp, mixing it with water and pouring it to the bio-digester. One 20-litre bucket of this mixture serves the bio-digester for four days.
A group member Eunice Kaparo, has set up a biogas plant at her homestead. She no longer uses firewood for cooking. She has also established a kitchen garden where she uses manure generated from the bio-digester to improve soil fertility.
“The beauty of the biogas project is that it is literally killing two birds with one stone. We are conserving the environment by not cutting trees for firewood, and also making a contribution towards controlling the spread of cactus on our land,” says Ms Kaparo.
The women group members have tasked Ms Kaparo with tending to the cochineal breeding project at the one-year-old greenhouse. The greenhouse was put up through support from Ol Jogi Wildlife Conservancy, in an effort to increase the predatory beetles’ population in the region.
The tiny beetles are bred in the warm greenhouse environment where they are introduced to pieces of cactus leaves to colonize, which is then dropped on the invasive plants in the fields. The tiny insects suck the sap, causing the drought resistant cactus to dry up.
The first insect breeding greenhouse was introduced in the locality in 2016. Five years later, the community complained that the insects, imported from South Africa, were not devouring the thorny –leaved plants as fast as expected.
“There has been little achievement in regard to eradicating opuntia since the introduction of the cochineal insects. The rate at which the succulent plant is propagating is faster than what is being eliminated,” Loise Kimiri, a local leader noted in 2021.
These concerns prompted women affiliated to Twala Cultural Manyatta to start the opuntia stricta eradication project, with the ultimate goal of influencing the community to take personal initiative and not become perennial complainants.
Cactus seeds are spread by livestock, baboons and elephants after consuming the purplish fruit and then disposing of the seeds through dung.
The cactus still occupies tens of acres in Makurian, Dol Dol, Mulpusi and Il Polei locations where both livestock and wild animals roam freely on these community land.
This exotic plant was introduced in parts of Laikipia County by colonialists in the 1950s, for fencing purposes and to control soil erosion in this semi-arid region. However, the local pastoral community now says it has caused them untold suffering as it continues spreading to new areas, suffocating grass and other indigenous vegetation, while causing deaths to sheep and cows that consume its fruits during drought.
Ms Nenini is optimistic that in the near future, individuals, women groups, education institutions and health facilities, will be supported to come up biogas plants, a step that would greatly assist in reduction of cactus.
Laikipia County Government is this year set to come up with a rangelands conservation policy, and a bill to legislate establishment of a kitty in the annual budget, to be channelled towards reclaiming rangelands affected by erosion and invasive plants.
Governor Joshua Irungu announced recently that this will commence immediately the Assembly resumes sittings next month (February).
“A single biogas unit costs about Sh200,000 inclusive of the motorised chaff cutter, bio-digester and piping of the gas. Majority of the members in our group cannot afford this installation in their homes, but the county government could target organized groups and public institutions for support in production of clean energy. This would be a double win for the community, the cactus would be weeded out, and the community will stop reliance on firewood and charcoal as the source of cooking fuel,” noted Ms Nenini.