Indigenous Knowledge and Development Monitor, 1993

CONTOUR HEDGEROW TECHNOLOGY IN THE PHILIPPINES: NOT YET SUSTAINABLE - S. Fujisaka P.A. Cenas

Contour hedgerows are used for soil erosion control in hilly agricultural lands in Asia, Africa, and Latin America. They have been introduced to farmers by development projects. There is little evidence for the existence of traditional or indigenous forms of this technology. A few farmers in the central Visayan region of the Philippines provide an exception; they used contour hedgerows of grass and trees to control soil erosion. But neither the traditional nor the introduced technology have proven successful. Farmers eventually abandon the fields for a number of reasons: disturbance caused by grazing animals, a need for fuelwood, and soil depletion, for example. The problems farmers experience in using this technology, be it traditional or modern, should be addressed by additional research.

Several methods for reducing soil erosion on sloping lands have evolved. These include bench terraces (Hudson, 1971; UACP, 1987) and alley cropping--in which tree biomass is used to protect soil and improve soil nutrient cycling (Huxley, 1986; Kang and Wilson, 1987; Young, 1986, 1987). A third method calls for contour hedgerows, which may or may not include trees (Abujamin et al, 1985; Fujisaka, 1989a, b; Hudson, 1990; Tacio et al, 1988, Grimshaw, n.d.; Smyle and Magrath, 1990). Although researchers have examined farmers' indigenous soil conservation methods (MacKay, 1990; Ramriez, 1988), there has been little evidence that farmers developed and used contour methods in the past.

Researchers from the Visayas State College of Agriculture (ViSCA) and from the International Rice Research Institute (IRRI) have formed the Upland Rice Research Consortium and are working together in Matalom, Leyte, Philippines. ViSCA researchers report that farmers in Matalom practised an indigenous contour hedgerow technology (Ly Tung and Alcober 1991, Ly Tung, personal communication). As part of the consortium's research activities and in support of IRRI's work with farmers in other areas, IRRI researchers sought out Matalom farmers who had developed or adopted the technology in order to learn how and why they started it and what had happened.

Interviews

Twenty-eight farmers from the municipality of Matalom were identified as having adopted contour hedgerow methods: 16 from the barangay (village) of Altavista and 12 from the barangay of Templanza. Farmers were informally interviewed and their fields visited. The researchers' aim was to learn when, why, and how the contour technologies were developed, introduced, or adopted. Farmers were also questioned about what had happened since adoption, and about their opinions of the technology. In-depth interviews were conducted with the eight farmers who claimed to have developed the contour hedgerow technology on their own.

Eight innovators

Eight farmers reported that between 1944 and 1977 they had individually and on their own developed and adopted contour hedgerows. The general practice was to leave narrow, curved strips of land unplowed. The weeds and grasses left to grow on them would form hedgerows that reduced soil erosion. None of the farmers used an A-frame or other similar device to lay out the contour lines. They relied instead on visual estimates. Although seven of the eight relied on hedgerows consisting largely of natural weeds and grasses, three also planted coconut palms and one planted Leucaena leucocephala in the hedgerows.

Six of the eight farmers had stopped cultivating the fields with hedgerows. The other two had abandoned upper terraces and hedges while continuing to cultivate lower alleys. The reasons they gave for abandoning fields with hedgerows were 1) the fields were disturbed by neighbours' animals, 2) soil became depleted, 3) soil erosion on upper slopes was not halted, 4) cultivation was moved to flatter parcels on the same farm, and 5) farming activities declined when children left home. Each of the eight innovators told a similar story; the following is a synthesis of their accounts:

'I constructed hedges (kahon kahon or samento samento) in 1955 after observing that soil was carried downslope by heavy rains. The method was to leave narrow unplowed strips along the contours and to plow and crop the areas between the resulting hedgerows of natural grass. The technology was my idea; I neither received advice nor copied from others. Unfortunately, grazing animals destroyed the hedges, and the soil in the cultivated areas eventually became depleted. This is why I quit cultivating the area'.

Twenty other farmers with hedgerows

Thirteen farmers in Altavista adopted contour hedgerows after technicians from the Philippines Department of Agriculture introduced a form of the technology in 1983 featuring the A-frame and L. leucocephala trees. In Templanza, seven farmers adopted contour hedgerows after learning about the technology from various sources. Almost all of the fields that were contoured have also been abandoned or left fallow because: 1. Neighbours' animals grazed in the area and destroyed the hedges. 2. L. leucocephala was allowed to grow to provide firewood. 3. Fields were left fallow to allow soil nutrients to regenerate.

Discussion

The fact that farmers developed methods for controlling soil erosion on sloping lands in Matalom clearly indicates first, that soil erosion is a local problem and one that farmers are well aware of, and second, that farmers actively seek and develop solutions to their problems. The hedgerows of in situ grasses and weeds that were created when farmers left strips unplowed are consistent with the method farmers in Claveria, Misamis Oriental, the Philippines, developed after being introduced to more complicated contour technology (Fujisaka, to be published).

Most importantly, farmers' reasons for abandoning the contoured parcels point to problems which farmers and researchers will have to solve: 1. Some of the innovators reported continued erosion from the steeper, higher fields. Their failure to use a simple A-frame to lay out contour lines more accurately could have resulted in 'dips' in the lines, which in turn could have exacerbated gully formation. The now widespread dissemination of the A-frame by organizations working with farmers to control soil erosion would seem to be appropriate. 2. Destruction of hedgerows by neighbours' animals was also a major problem in systems developed by farmers in Claveria (Fujisaka, to be published). The problem could indicate a need for entire communities to adopt the method, and for the coordination of land conservation efforts. 3. Farmers' conversion of parcels with tree-based hedgerows into woodlots for fuel has not, to our knowledge, been reported elsewhere. The same result might be expected in other areas where farmers have other lands to cultivate and where fuelwood is a crucial need. 4. Matalom farmers abandoned sloping parcels with hedgerows in favour of working on their level land. Similarly, Claveria farmers who had been trained in contour hedgerow methods but who subsequently failed to adopt the technology had more, and a higher proportion of, flatter land (i.e., with slopes of less than 12%) (Fujisaka, to be published). The implication in both cases is that the technology should be targeted on farmers without flatter land. 5. Matalom farmers abandoned fields with contour hedgerows because of soil nutrient depletion. Recently, some Claveria farmers abandoned contoured fields in favour of renting the use of fields that had not been continuously cropped. Both cases indicate that stopping soil erosion does not solve the problem of soil nutrient depletion in permanently cropped systems. Alley cropping systems in which farmers incorporate biomass from N-fixing trees were not adopted in Claveria because of the labour required. The situation was presumably similar in Matalom. On the other hand, some Claveria farmers switched to high-value crops and the use of inorganic fertilizer on their contoured fields after soil fertility declined. Overall, and perhaps unfortunately, biomass recycling is adopted only when farmers do not have other lands available, labour costs are relatively low, and inorganic fertilizer prices are high (or inorganic fertilizers are not available).

In view of the fact that a) the natural grassy strip technology was spontaneously developed by Matalom farmers, and b) the same technology was developed by Claveria farmers in response to exposure to a more complex contour hedgerow system, ViSCA scientists are working to improve and extend the technology (Ly Tung and Alcober 1991). At the same time, IRRI researchers are working to determine the particular agro-ecosystems and conditions where such natural vegetative contour technologies would be appropriate.

Conclusions

Farmers' innovations are easily identifiable as starting points for agricultural research (Fujisaka, 1991). The present case is of particular interest because the farmers' innovation--in this case natural vegetative contour strips to control soil erosion--'failed' (in the sense that such fields were abandoned or allowed to lie fallow) for a number of technical reasons. In both Claveria and Matalom, grazing by neighbours' animals, soil nutrient depletion, and the availability of flatter land resulted in the abandonment of countoured fields. The conversion of tree-based hedgerows to woodlots in Matalom was also an unforeseen result of an initial attempt to control soil erosion. These 'negative' results each provide specific topics for additional research on contour hedgerow systems, not only in Matalom or Claveria, but also in regions of Asia, Latin America and Africa where conditions are similar.

S. Fujisaka P.A.Cenas Agricultural Anthropology Social Science Division International Rice Research Institute P.O. Box 933 1099 Manila The Philippines Fax: +63-2-8182087

References

Abujamin, S., A. Abbdurachman, and Suwardjo (1985) 'Contour grass strips as a low cost conservation practice', ASPAC Extension Bulletin 221:1-7.

Fujisaka, S. (forthcoming) 'A case of farmer adaption and adoption of contour hedgerows for soil conservation', Experimental Agriculture.

Fujisaka, S. (1991) 'What does 'build research on farmer practice' mean? Rice crop establishment (beusani) in eastern India as an illustration', Agriculture and Human Values 8:1, 2:93-98.

Fujisaka, S. (1989a) 'The need to incorporate farmer perspectives: reminders from selected upland projects & policies', Agroforestry Systems 9:141-153.

Fujisaka, S. (1989b) 'A method for farmer-participatory research & technology transfer: upland soil conservation in the Philippines', Experimental Agriculture 25:423-433.

Grimshaw, R.G. (n.d.) Vetiver grass (Vetiveria zizanioides): a method of vegetative soil and moisture conservation. New Delhi: World Bank.

Hudson, N.W. (1990) 'Soil conservation projects: success or failure?', Contour 2:2:3-6.

Hudson, N.W. (1971) Soil Conservation. London: BT Batsford Limited.

Huxley, P.A. (1986) Rationalising research on hedgerow intercropping: an overview. Nairobi: International Council for Research on Agroforestry (ICRAF) Working Paper 40.

Kang B.T. and G.F. Wilson (1987) 'The development of alley cropping as a promising agroforestry technology', in H.A. Steppler and P.K.R. Nair (eds) Agroforestry: A Decade of Development. Nairobi: ICRAF.

Ly Tung and D. Alcober (1991) 'Natural grass strips are preferred', ILEIA Newsletter 1991:1,2:27-28.

MacKay, K. (1990) 'Philippines', Sustainable Agriculture Newsletter 2:2:26-28.

Ramirez, D.M. (1988) Indigenous soil conservation strategies in Philippine upland farms. Environment and Policy Institute, East-West Center Working Paper 1.

Smyle, J.W. & W.B. Magrath (1990) Vetiver grass: a hedge against erosion. Paper, American Society of Agronomy Annual Meetings, San Antonio, Texas, 22 October 1990.

Tacio, H.D., H.R. Watson and W.A. Laquihon (1988) 'Nitrogen- fixing trees as multipurpose species for soil conservation', in: D. Withington, K.G. MacDicken, C.B. Sastry, N.R. Adams (eds) Multipurpose Trees for Small Farm Use. Arlington, Virginia: Winrock International; Ottawa: International Development Research Centre.

Young, A. (1986) The potential of agroforestry for soil conservation. Part I. Erosion control. Working Paper 42. Nairobi: ICRAF.

Young, A. (1987) The potential of agroforestry for soil conservation. Part II. Maintenance of fertility. Working Paper 43. Nairobi: ICRAF.

Upland Agriculture and Conservation Project (UACP) (1987) Upland agriculture and conservation: research highlights 1985- 86. Bogor: Indonesia Ministry of Agriculture and USAID.

Acknowledgement

Dr. Edwin Balbarino of ViSCA provided invaluable assistance in the fieldwork activities.

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