Title :Management of Prosopsis juliflora Invasion through Charcoal Production using Improved Earth Kiln in Marigat Sub-County, Kenya
Audience :Farmers, Charcoal Producers, Extension Agents
Category :Land Management
Marigat Sub-County in Baringo County lies between latitude 00 20’N and 00 44’N and longitude 350 57’E and 360 12’E. The altitudinal range of the area is between 900 and 1,200 m above sea level. The area is generally hot and dry throughout the year. Rainfall variability is very high with an annual average rainfall of about 650 mm. Most of the rain falls within one season from April to August, followed by a prolonged dry season. The rainfall pattern is strongly influenced by local topography. Temperatures within the Sub-County range from 30oC to 35oC but can rise to 370 C in some months, with the hottest period being between January and March. Soils comprise mainly of clay loam and alluvial deposits.
Charcoal production from wood is one of the major economic activities in drylands of Kenya. In many areas, the practice is not sustainable due to over exploitation of trees from the woodlands. However, in Loboi Location, Marigat Sub-County, charcoal production is sustainably undertaken through use of Prosopsis. Prosopis was introduced in the area in 1980’s for use as a windbreak and to reclaim degraded areas. With time, the species became invasive, and suppressed undergrowth which led to reduced livestock feed. To control Prosopis invasiveness, the community in Loboi embarked on managing the species through charcoal production, an activity usually carried out through groups. One such group is LOKASACHA Charcoal Producers Association, which started producing Prosopis charcoal using traditional earth kilns in 2011. However, this type of kiln has a low recovery rate of about 15 -20% and causes environmental pollution through the smoke emitted. To improve charcoal production efficiency in Loboi, Kenya Forestry Research Institute (KEFRI) introduced and trained the Group on use of improved earth kiln. The improved kiln is fitted with chimneys and air inlet pipes, has a recovery rate of 26 - 30%, produces charcoal of higher quality and has reduced smoke emission.
Management of Prosopis invasiveness through sustainable charcoal production using improved earth kilns.
The tools required for production of Prosopis charcoal include; power saw, axe, panga (machete), spade, jembe (hoe), chimneys, metallic air inlet, and sacks.
Procedure for producing charcoal using improved earth kiln
1. Identify an area with Prosopis trees suitable for charcoal production.
2. Clear bushes and cut the Prosopis trees.
3. Cross cut the trees into pieces of 1 - 1.5 m length.
4. Lay three poles on a cleared leveled ground to act as a base.
5. Arrange pieces of wood across the poles starting with the largest to make a stack.
6. Place two metallic air inlet pipes between the poles on either end of the heap of wood.
7. Fit the chimneys firmly in the heap of wood.
8. Place grass evenly on the stack to completely cover the wood.
9. Cover the grass with soil to a depth of about 20 cm leaving an open space for lighting fire (lighting point).
10. Light fire through the lighting point
11. Close the open space (lighting point) with soil.
Note: After 3 - 4 days, blue smoke will appear through the chimney indicating that the wood has been converted to charcoal.
12. Put off the fire by sealing the chimney and any other open space. Allow the kiln to cool, while ensuring it is air tight so that the charcoal does not burn.
13. Remove soil covering the kiln.
|Harvesting propopis trees for charcoal making
||Demonstration of laying down the base of earth kiln
|Prosopis wood in a kiln
||Illustration of an improved earth kiln
|Charcoal ready for repackaging
||Packaged charcoal ready for sale
• The invasion by Prosopis species has been managed through charcoal production.
• Increased productivity of woodlands as grass is regenerating in pastureland previously under Prosopis.
• More land freed from Prosopis is now available for crop production.
• Community members have increased income from sale of; charcoal, livestock and crop produce.
• The improved earth kiln produces less smoke, making it environmentally friendly.
• Employment opportunities for community members
• Prosopis produces a lot of biomass within a short time, which ensures continued supply of raw material and consequently sustainability of the practice.
• The charcoal produced using this technology is of high quality and has a ready market.
• Presence of charcoal producers associations ensures bargaining power for suitable prices, which is a motivation for farmers to continue with the practice.
• The practice is labour and capital intensive
• Legal huddles in transportation of charcoal
• Charcoal production can be used to manage Prosopis invasion.
• Use of improved earth kiln minimizes air pollution.
• The improved kiln produces high quality charcoal and has a higher recovery rate compared to traditional earth kiln
Use of improved earth kiln is a viable option for charcoal production from Prosopis species. The practice is efficient, environmentally friendly and produces high quality charcoal, leading to increased income and improved livelihood.