Field Guide of Discovery-based Exercises for - Aseanipm ...

Exercise No. 3.16 85
BENCH TERRACING AS A SOIL CONSERVATION
STRATEGY FOR HIGHLAND ORGANIC VEGETABLE
PRODUCTION
BaCKGroUND aND raTIoNalE
Terracing is the most effective erosion control measure
practiced in the Cordilleras. If properly designed and
constructed, terraces can reduce soil losses to about oneeight
of what it would be with no erosion control measure.
Land that is moderately sloping and subject to moderate
or severe erosion would require use of terraces such as
114
Field Guide of Discovery-based Exercises for Organic Vegetable Production
those in Ifugao and Mountain Province. Forming a series of banks breaks down a long slope.
Drainage ditch at base of each bank conduct water around slopes. Such areas may have slopes of 20
% or more. Of the different types of terracing that can be done, bench terracing is the most intensive
form and is applicable to small organic vegetable areas.
Bench terracing consists of creating a series of level strips running across slope. Viewed from a
distance, it looks like a stairway. Each terrace is separated by an almost vertical retaining wall of
earth, rock, or concrete protected by vegetation. Bench terraces are sometimes provided with silt
pits or soil traps, which are actually short canals, constructed after every few rows of vegetable
crops to slow down the flow of water and catch soil washed downhill. Soil that accumulates in pit is
regularly removed and thrown up to form a dike, especially before the rainy season 86 .
Farmers in highlands are continuously adapting more innovative bench terracing practices for long
sloping areas, which when shared with others in FFSs will further improve existing best practices.
This exercise was so designed to enhance such sharing of experiences.
How long will this exercise take?
when is this exercise most
appropriate?
ɶ In FFS, TOT, and VST
sessions, before land
preparation and laying-out
in learning field; and
ɶ When farmers want to learn
from other farmers some
innovative bench terracing
practices for organic
vegetable production in long
sloping areas.
• Thirty minutes to one hour for field walks, observations, and interaction with farmers in
adjoining fields of learning field;
• Thirty minutes for brainstorming session in processing area; and
• As needed for hands-on in farmers’ own fields.
85 Adapted from Callo, Jr., D.P., L.B. Teofilo, and H.A. Tauli (eds). 2002. Field Guide of Discovery-based Exercises for Vegetable IPM, Volume II. SEAMEO
Regional Center for Graduate Study and Research in Agriculture (SEARCA), Los Baños, Laguna, Philippines. pp101-104.
86 Bautista, O.K. (ed). 1994. Introduction to Tropical Horticulture. 2 nd Edition, SEAMEO Regional Center for Graduate Study and Research in Agriculture
and University of the Philippines Los Baños, College, Laguna, Philippines. pp310-312.