A government initiative to plant 10 million tree seedlings to restore 140,000 hectares of a degraded Maasai Mau Forest was to commence on November 1.
Rampant illegal encroachment over the years has left the water tower vulnerable, raising a critical environmental concern at a time of unforgiving negative effects of climate change.
The ecosystem’s restoration is aimed at reviving the several rivers, including in neighbouring countries, that it sustains, some of which have dried up.
Environment Cabinet Secretary Keriako Tobiko, while announcing the campaign, also called for donations of tree seedlings. But some issues need to be given consideration.
Restoration of the Mau will require planting of ecologically suitable tree species, the equivalent of the remnants of the ecosystem. We are not only increasing the vegetation cover. We must plant diverse tree species that easily grow in this ecosystem and can withstand pests and diseases. Aim also to promote the restoration of associated indigenous plants and animals.
Without the knowledge of the species, it is possible for the donors to give seedlings of trees that are not indigenous to the region — such as eucalyptus, cypress and pine, which are common in local nurseries.
Taking this precautionary measure will prevent negative ecological impacts as experienced with the introduction of Prosopis juliflora (“Mathenge”) in the arid and semi-arid lands (ASALs) in the 1970s. Mathenge was brought from South America for ecological rehabilitation, but turned to be invasive and became a livelihood and environmental menace.
Considering the tree lifespan, such negative effects may only be realised 20-30 years later.
For guidance, a “Mau restoration species checklist” should be prepared and made available to interested parties. Kenya Forest Service (KFS) has the resources to do that.
Local nurseries should be involved in raising the required seedlings. Besides easing transport and other logistics, documenting the nurseries and the tree species they deal with will facilitate the selection. They should then be facilitated with resources such as good quality seeds and water, if necessary. Also ensure that the seedlings are at a good planting stage.
On a national scale, the call to increase the forest cover should be backed by initiating a tree seed and seedlings system that would advise on planting the right tree in the right place. The biggest impediment to tree planting is insufficient knowledge of the species and availability of quality seeds or seedlings.
Promoting tree diversity also needs to be emphasised. It will enhance mitigation of the adverse effects of climate change as different tree species will have different phenology (leafing, flowering and fruiting) times. That influences the microclimate and makes it suitable for other farming activities, as well as offer varying products to the farmers.
With decreasing indigenous forest land, the future forests will be on farms. Through agroforestry (tree on farm), the tree cover in catchment areas will be more easily restored. It is upon the government to explore ways of reaching this goal.
Mr Kang’ethe is an environmental scientist at World Agroforestry (ICRAF), [email protected]