Contour Grass Hedgerows on Steep Slopes
Type: Technologies
Creation: 2023-07-15 04:24 Updated: 2024-06-04 14:44
Compilers: ONGPO LEPCHA
Reviewers: William Critchley, Rima Mekdaschi Studer, Joana Eichenberger
Country/ region/ locations where the Technology has been applied and which are covered by this assessment
- Country: Bhutan
- Region/ State/ Province: Mongar
- Further specification of location (e.g. municipality, town, etc.), if relevant: Boucholing village, Thangrong gewog (block), Mongar Dzongkhag (district)
- Map: View Map
Description of the SLM Technology
Short description of the Technology
Contour hedgerows are a soil and water conservation technology that involve planting of Napier grass cuttings along contour lines on the slope at a horizontal distance of 6 m. The area between the contour hedgerows is used for crop cultivation.
Detailed description of the Technology
Contour hedgerows are a soil and water conservation technology that involves planting Napier stem cuttings along contour lines on slopes. They are planted at a horizontal distance of 6 meters between rows and 15-20 centimeters between cuttings within lines. On average it requires 3500-4000 Napier slips to cover one acre (0.4 ha). Hedgerows form living barriers that trap sediment and reduce surface runoff. With time, as the sediment builds up behind the hedges, the area between the hedgerows develops into flat alleys or “terrace beds”. This technology is effective in reducing soil erosion and conserving water. The hedgerows also boost crop productivity. The contour hedgerow system is widely used in hilly terrain in Bhutan and elsewhere.
The main purposes of the technology are to 1) serve as a barrier to check the movement of soil and water down the slope, 2) effectively utilize sloping areas for agricultural purposes, and 3) increase crop and fodder production.
The major activities/ inputs needed to establish/ maintain contour hedgerows are: 1) surveying of the area by an SLM specialist (planning and site assessment), 2) selecting suitable hedgerow planting materials, 3) registration of interested farmers, 4) training of farmers, 5) layout of contour lines using A-frames, 6) distribution of planting materials and establishment of hedgerows in farmland, 7) monitoring and evaluation of hedgerows, and 8) maintenance of hedgerows. Maintenance includes replacement of cuttings in gaps - either damaged by cattle or natural mortality and trimming of grass back to 15 centimeters after reaching 1 meter. Inputs required include: 1) planting materials (Napier grass), 2) A-Frame for contour lines, 3) spades, pickaxes, shovels, crowbars, etc., and 4) human resource input by SLM specialists.
Contour hedgerows have many benefits/ impacts on the livelihood of the land users including 1) soil and water conservation, 2) use of the sloping areas for crop or fodder production, 3) effective conservation through using local materials with a 90% survival rate, 4) habitat for natural predators, pollinators, insect-eating birds, and rodent predators, 5) groundwater recharge, and 6) they beautify the overall agricultural landscape. Another important benefit of the hedgerows is the availability of fodder grass for livestock, which otherwise would have to be collected from the forest. The disadvantages include the need for regular maintenance and gapping up. At times, conflicts arise within the community due to grazing of hedges by neighbors’ cattle.
Photos of the Technology
- 📍 Boucholing village, Thangrong gewog (block), Mongar Dzongkhag (district), Bhutan
- 📷 Tashi Wangdi & Chenga Tshering
- 📍 Boucholing village, Thangrong gewog (block), Mongar Dzongkhag (district), Bhutan
- 📷 Tashi Wangdi