No. 41, Spring/Summer 1997
The CCD, Part II: Asia & Americas
by Jay B. Norton and Jonathan A. Sandor
"Zuni agriculture represents a long-term successful land conservation strategy (....) [utilizing] the exodus of eroded soil and water resources from pinyon-juniper uplands to grow food that sustained their people."
Desertification in the southwestern United States is a controversial issue: is degrading environmental quality the result of human activity or of natural climatic and erosional cycles? A protracted court case, the United States vs. the Zuni Tribe, provides a compelling illustration of the polarized nature of the controversy. Advocates of human activity as the cause of desertification prevailed in this case when the U.S. government paid retribution to the Zuni tribe, creating the Zuni Land Conservation Act of 1990 (Hart, 1995).
As a result of the Act, the Zuni Conservation Project (ZCP) has begun work toward sustainable natural resource development on the reservation (Enote et al., 1993). The approach combines local knowledge with scientific study of natural resources to fight desertification and to revitalize agriculture as an economic entity. The once important traditional practice of runoff agriculture holds promise for both endeavors: combating desertification through mitigation of erosion, sedimentation and flooding while improving crop and forage production by utilizing eroded soil and water resources.
While large scale movement of sediment has been a dominant process in formation of the Southwest's mesas and canyons through geologic time, the construction of permanent reservoirs turned this natural process into an expensive problem. In their eagerness to capture and store valuable water resources, early government engineers on the Zuni Reservation failed to recognize the other valuable resource leaving the uplands with runoff or the menace it poses to permanent dams across Zuni water courses. Soil eroded from Zuni lands has filled every impoundment built for irrigation, flood control, or erosion control, rendering them nearly useless and often causing washouts and further erosion of stream courses.
This article describes an interdisciplinary effort that recognizes the value of local knowledge in dealing with local natural resource issues. The effort combines Zuni farmers, Tribal natural resource managers, and research sponsored by the National Science Foundation.(Back to top)
The Zuni Indian Reservation lies within the Colorado Plateau on the western slope of the Zuni Mountains in the mesa country of western New Mexico. Elevation ranges from 1838 meters (6030 feet) near the Arizona border to 2347 meters (7700 feet) on eastern mesas, near the continental divide. Average annual precipitation ranges from 300 to 400mm (12 to 16 inches), with over half coming in July, August, and September. During this period, known locally as the monsoon season, moist air moves over the hot and dry southwestern uplands, generating very localized convection rainstorms that can be frequent and intense. The storms are especially erosive because the semiarid climate supports only sparse ground cover vegetation. The remainder of each season's precipitation comes as snow and low-intensity rain during fall, winter, and early spring. May and June are typically dry.
Beginning in the 1880's, geomorphic processes in the Southwest entered an erosional period after a long period of stability and aggradation (Bryan, 1925; Cooke and Reeves, 1976; Leopold et al., 1966). Regardless of the polarization on this issue, both natural and human-caused factors have been shown to contribute to the desertification process. Severe downcutting of ephemeral stream channels is the most noticeable and well documented manifestation of the problems, but drastic shifts in vegetation toward woody shrubs, lowering of local water tables, and severe wind erosion are also well documented, as is major and expensive sedimentation in the many reservoirs. Dramatic examples of all these desertification processes are both obvious and well documented on the Zuni Reservation (Hart, 1995).(Back to top)
Many generations of Zuni farmers have harvested runoff from the summer storms to grow corn (Zea mays) and other crops. As with other Native American agriculturalists of this region, Zuni runoff farming uses no fertilizer or irrigation in the conventional sense. Farmers credit the ephemeral stormwater flows, which they divert onto well-placed fields, with supplying moisture and nutrients to produce crops.
Zuni agriculture is intertwined with all aspects of Zuni culture and has a long and rich history. Written accounts begin with the expedition of Coronado in 1540. In a letter to Viceroy Mendoza in Spain Coronado writes, "(the people) are all well nurtured and condicioned.... The victuals which the people of this countrey have, is Maiz, whereof they have great store...." (Cushing, 1920). Corn grown in runoff fields was the staple crop, but Zuni farmers and gardeners grew many other crops, including beans, squash, melons, peppers, and, after European contact, wheat and peaches. All of these crops and more are still produced on the reservation but at a much smaller scale than previously, when agriculture was the mainstay of Zuni subsistence.
The next conquerors to invade Zuni territory also appreciated Zuni farming prowess. From 1850 to 1870 recently established U.S. military installations created an excellent market for grain (McCall and Frazer, 1968). Ironically, the resulting peak in production could have contributed to the demise of runoff agriculture at Zuni. This early introduction of Zuni society to a cash economy led to a peak in corn production for the 20-year period with as much as 10,000 acres of runoff-fed corn under cultivation. The demise of the grain market as Anglo farmers became established in the region may have led Zunis to pursue other cash markets, such as jewelry production, over subsistence farming. Other factors that may have contributed to the decline in agriculture include devastating smallpox epidemics around 1900, U.S. policies aimed at assimilating native cultures, and a shift toward livestock production on the reservation (Cleveland et al., 1995).
Conventional agricultural development itself is one of the primary reasons for the decline of Zuni agriculture (Cleveland et al., 1995). Construction of irrigation reservoirs and reallottment of lands into agricultural lands (irrigable) and grazing lands (much of the traditional runoff farms) disrupted the indigenous land tenure system, creating contentious land disputes that prevent much land from being used and that persist to this day.
While there are excellent irrigated fields where high quality alfalfa is produced, much of the irrigable land on the reservation lies on clayey soils of the major valleys where proper irrigation is not feasible even if water is available (NRCS, in press). Water is very scarce, however, because sedimentation has diminished water storage behind most of the dams to a fraction of their original capacity. Besides shrinking the irrigable area, the diminished capacity creates serious dam safety concerns.
Runoff agriculture refers to methods of collecting and spreading ephemeral stormwater for crop use after each runoff-generating event. The techniques traditionally used in the Southwestern U.S. focus on diversion and spreading of concentrated ephemeral flows with combinations of brush weirs and stone check dams (Nabhan, 1984). Other techniques, as of the ancient farmers of Israel's Negev Desert (Evenari et al., 1982) and modern water harvesting techniques, focus on catchment soil modifications that maximize overland flows and concentrate them onto small fields or orchards. In general, runoff harvesting is an important technique where direct rainfall alone is insufficient to meet crop water requirements; extra water from a larger catchment area can supply the difference. Runoff agriculture dates back more than one thousand years in arid regions such as the Middle East (Evenari et al., 1982), northern Africa (Neimeijer, 1993), as well as the southwest U.S. and Mexico (Donkin, 1979; Hack, 1942; Nabhan, 1984; Sandor, 1995). Runoff agriculture, or waterspreading, is recognized as a water-conserving alternative to irrigated agriculture, and a way to restore degraded rangeland and combat desertification (Frasier, 1980; Kowsar, 1991; Nabhan, 1981; OTA, 1983; Tabor, 1995).
Archaeological and historical evidence shows that runoff farming was very common throughout the Southwest for over a millennium, until the early 20th century (Cordell, 1984). It was practiced by farmers of all the Pueblos and their ancestors as well as the Tohono O'odham and other tribes. Hispanic and Anglo farmers also adopted the practice (Bryan, 1929). Runoff spreading systems have been discovered at or near major archaeological sites including Chaco Canyon (Wells et al., 1983), Mesa Verde (Smith, 1987), and Casas Grandes (Herold, 1965). Remnants of prehistoric check dam systems are commonly associated with southwestern prehistoric settlements younger than AD 900 (Cordell, 1984; Sandor, 1995; Sandor et al., 1986a) Today, although on a smaller scale than in the past, runoff spreading techniques are commonly used by the Tohono O'odham (Nabhan, 1984), Hopi (Hack, 1942; Manolescu, 1995; Stewart, 1940), and Navajo tribes of Arizona and the Zuni (Norton, 1996; Pawluk, 1995; Stewart, 1940) and other Pueblo tribes of New Mexico. The wide expanse of runoff agriculture in both time and space suggests that a large portion of the alluvial fans in farmable zones of the Southwest had active runoff spreaders at some time during the last millennium, although perhaps maintained only on a very long cycle of cultivation.
The extent of runoff agriculture in the Southwest declined dramatically during the 20th century and has been considered a victim of the accelerated erosion because deep incision of ephemeral stream courses can prohibit waterspreading practices (Bryan, 1929). On the Zuni Indian Reservation, however, many traditional runoff agricultural areas are not incised, although most have been abandoned within the last 120 years. Incision begins down slope in higher order streams. A combination of social and economic factors may better explain the decline in rain-fed farming than downcutting of arroyos. As such, contrary to Zuni runoff agriculture being a victim of desertification, its decline may be one of the contributing factors to desertification in this area. This traditional farming practice actually thrives on the movement of soil and water resources. A return to traditional farming methods could help to alleviate expensive erosion, sedimentation, and flooding problems while actually retaining and utilizing the stream of soil and water resources currently leaving Zuni land after each rainstorm.
Three lines of attack are exploring the use of Zuni runoff agriculture principles in combating desertification:
The long-term experience of Zuni agriculture may hold the most effective tools for combating local desertification problems. However, as with many indigenous cultures, decades of conventional agricultural development have disregarded this body of knowledge so that much has been forgotten or has lost credibility, even among those who remember the techniques (Pawluk et al., 1992). One way for such traditional conservation techniques to be considered on a plane with conventional, often less culturally appropriate, methods is documentation of scientific bases. Local people who are expected to lend knowledge, labor, and land and who must deal with desertification on a daily basis must be the first and most direct benefactors of this type of research. Also, indigenous knowledge like Zuni runoff agriculture is often part of complex language, religious, and sociological systems that are not possible or appropriate for scientists to study or understand. But, after many decades of disregard, study of the ecological operation and long-term ecological effects of indigenous techniques is often necessary to reintroduce them as legitimate alternatives. Close collaboration with indigenous farmers and local officials is essential in order to maintain cultural sensitivity necessary for such research.
National Science Foundation research is exploring the long-term soil effects, productivity, and underlying ecological processes of Zuni runoff farming. As some of the oldest continuously farmed and well documented agricultural fields in the U.S., Zuni runoff fields offer an excellent opportunity for examining effects of long-term cultivation on soils. Preliminary evidence from comparison of range soils to those farmed since prehistoric times suggests that soil quality has not suffered from many centuries of Zuni runoff agriculture. In contrast, studies of soils under less than one century of conventional dryland cultivation show drastic declines in soil quality attributes such as solum thickness and organic matter content (Aguilar et al., 1988). While more study is needed before conclusions can be drawn, the data suggest potential for long-term runoff agriculture without degradation of soil productivity.
Although hydrologic measurement and water balance calculations of runoff agriculture have been done (Evenari et al., 1982; Perrier, 1988), there has been little quantitative work on fertility aspects. Limited work on prehistoric and current Native American runoff farming sites suggests the importance of runoff farming in not only contributing water but also replenishing nutrients in fields (Nabhan, 1984; Norton, 1996; Pawluk, 1995).
A primary objective of the research is to evaluate nutrient transport and delivery from watersheds to fields. Preliminary investigations of one runoff field and its contributing watershed have revealed soil-landscape-vegetation relationships that enhance the movement of runoff and organic matter toward agricultural fields. For example, much of the watershed study area is characterized by thin A horizons over well developed argillic horizons on steep pinyon-juniper (Pinus edulis and Juniperus spp.) wooded slopes with little ground cover vegetation. This combination of low soil permeability, steep topography, and forest litter deposition may be a major factor in the maintenance of soil fertility and moisture in fields located on depositional areas below.
Data from a longitudinal transect on the alluvial fan show that the field is located in silty and fine loam textures, between sandier surfaces upslope and clayey surfaces closer to the main valley. Soil organic matter constituents (organic carbon and total nitrogen) in and near the agricultural fields are most highly correlated with the silt content of the samples (r = 0.75 and 0.81 respectively), rather than clay content (r = 0.30 and 0.44 respectively) as is more common for these materials. This correlation diminishes upslope from the field. These data may reflect co-deposition of silt size particles and organic matter by water, possibly emphasizing the importance of alluvial deposition in soil fertility maintenance.
Soil storage of runoff water is important both in increasing soil productivity on headwater alluvial fans and reducing downstream erosion, sedimentation, and flooding. A preliminary look at soil moisture across two farmed alluvial fans without actively maintained waterspreading systems shows that soils have higher moisture content through the middle of the fans, where shallow watercourses carry ephemeral flows. This corresponds with observations of color aerial photographs that show narrow green strips bisecting nearly every unincised alluvial valley. Conceptually, this green zone could be widened with active waterspreading. Soils would store a great deal more of the runoff now flowing over the alluvial fans and through the incised water courses. Data from the recent USDA soil survey (NRCS, in press) indicate that soils of alluvial fans in the study area could potentially hold one acre-foot of water per acre of soil in the upper 6 feet of the solum. With efficient waterspreading and, possibly, other infiltration enhancement practices this soil could store much of the runoff from small headwater drainages, potentially mitigating downstream gully erosion, sedimentation, and flooding. Crop production studies beginning this year will help to reveal onsite profitability of runoff spreading. Earlier studies of rangeland waterspreading indicate economic benefits from increased forage production (Miller et al., 1969).(Back to top)
Traditional waterspreading technology is subsistence oriented and labor-intensive. Brush weirs and stone check dams built by hand are effective, but maintenance requirements are high. Combining the traditional technology and native materials with tractor power for installation, for example, may reduce maintenance requirements of the spreading systems.
The Zuni Conservation Project has designed and installed many types of erosion control structures based on traditional methods and native material. They monitor the success of these structures and have found that they do very well. Conventional structures, on the other hand, have been found to be short-lived and often exacerbate erosion and sedimentation problems (Gellis et al., 1995). ZCP staff have installed waterspreaders to increase forage production, enhance wildlife habitat, and increase groundwater recharge to enhance flow at springs.(Back to top)
The farmer-run Zuni Sustainable Agriculture Project has been working with funding from the Ford Foundation since 1990 to identify obstacles to Zuni farming and implement programs to revitalize agriculture. The primary activities of the project include:
Education and Awareness: Educational programs of both youth and adults are considered among the most important activities of ZSAP by its leaders. Reconnecting the strongly agricultural-based Zuni religion to actual dependence on soil and water resources is seen as essential to the future of Zuni culture. The ZSAP staff have worked hard to raise awareness and credibility of Zuni agricultural knowledge in the community. They have conducted extensive interviews with Zuni elders and created a database of Zuni agricultural knowledge. Traditional waffle-bed gardens have been established at elementary schools and the Zuni Museum. Paramount to acceptance of ZSAP programs in the community is acceptance by Zuni religious leaders. The directors of ZSAP interact with these individuals and act on ideas and suggestions from them.
Technical Assistance and Equipment: The staff receives training in irrigation and cultivation practices and interprets this information to Zuni farmers in workshops and newsletter articles. The biculturality of ZSAP leaders enables them to choose and interpret technologies appropriate to Zuni experience, belief, and environment. After a lack of access to farm equipment was identified as one of the main obstacles to farming, ZSAP raised funding through the Lannan Foundation to purchase a tractor, manure spreader, grain drill, tiller, and other equipment for use by Zuni farmers.
Access to Irrigation: Lack of access to irrigation water is another of the main obstacles to farming identified. ZSAP has developed a task force of BIA (Bureau of Indian Affairs), tribal government, and farmers to work on more equitable policies for distribution of water. They have worked to identify the water resources available and ways to improve the efficiency of irrigation systems. ZSAP has also worked to reawaken Zuni farmers to the importance of non-irrigated agriculture on the reservation.
Marketing: After being approached by people interested in buying organic Zuni-produced grains and vegetables, ZSAP has developed an organic growers group and worked with the New Mexico Organic Commodity Commission to streamline the certification process for small farmers on the reservation.
Over 20 farmers planted plots of winter wheat in the fall of 1995. The crop was lost, along with winter wheat across the west, to the drought of spring 1996. But, undaunted, the organic growers group is even larger this year and planted even more winter wheat in the fall of 1996.
Land Disputes: The biggest obstacle to farming cited by Zuni people is land disputes. It is often not clear who controls what land. Boundaries have often been forgotten or are remembered differently by adjacent land users. In a huge effort, ZSAP has mapped field boundaries in Zuni's five farming districts with Global Positioning System equipment and created a database of Zuni agriculture. The database is constantly updated as more information is gathered about land use rights and history.
The Zuni Sustainable Agriculture Project is successful in large part because the leaders and staff are grassroots Zuni farmers who have experienced traditional farming life at Zuni and are devoted to passing on this tradition. As lifelong members of the community they understand the task of revitalizing Zuni agriculture as no outsider can.(Back to top)
Zuni agriculture represents a long-term successful land conservation strategy with a 100-year hiatus. For over 1000 years Zuni farmers utilized the exodus of eroded soil and water resources from pinyon-juniper uplands to grow food that sustained their people. As Zunis abandoned traditional farming methods to cope with repression and misguided development strategies of the recent century's dominant culture, the nutrient-laden waters that previously supported them have become an expensive liability.
Now, as Zuni farmers once again take charge of their own resources and reintroduce modernized versions of time-tested traditional technologies, they can reestablish the centuries-old balance with their dynamic environment. The traditional practice of Zuni runoff agriculture may present an opportunity to convert processes currently perceived as degradative because of expensive erosion, sedimentation, and flooding problems into actual crop and forage production increases.
For the program to succeed in turning an environmental liability into an agricultural asset, the three parts, agroecological research, technology development, and agricultural revitalization, must continue to work closely together to demonstrate the technological legitimacy of the ancient traditional practice, to develop ways to implement the methods under today's constraints on labor and time, and to restore a social and economic environment conducive to agriculture.(Back to top)
We are grateful to Jim Enote and Kirk Bemis of the Zuni Conservation Project and to Andrew Laahty and Roman Pawluk of the Zuni Sustainable Agriculture Project for their careful review and thoughtful comments.
Zuni Conservation and Sustainable Agriculture Projects
P.O. Box 339
Zuni Pueblo, NM 87327
Fax: 505-782-2726 (Back to top)
Aguilar, R., E.F. Kelley, R.D. Heil, 1988. Effects of cultivation of soils in northern Great Plains rangeland. Soil Science Society of America Journal. 52: 1081-1085.
Bryan, K., 1925. Date of channel trenching (arroyo cutting) in the arid southwest. Science. 62: 338-344.
Bryan, K., 1929. Floodwater farming. The Geographical Review. 19: 444-456.
Cleveland, D.A., F.J. Bowannie, D.F. Eriacho, A. Laahty, E. Perramond, 1995. Zuni farming and United States government policy: The politics of biological diversity in agriculture. Agriculture and Human Values. 12: 2-18.
Cooke, R.U., R.W. Reeves, 1976. Arroyos and environmental change in the American Southwest. Oxford University Press, New York, pp. 213.
Cordell, L.S., 1984. Prehistory of the Southwest. Academic Press, New York.
Cushing, F.H., 1920. Zuni breadstuff. Museum of the American Indian: Heye Foundation, New York, pp. 670.
Donkin, R.A., 1979. Agricultural terracing in the aboriginal New World. University of Arizona Press, Tucson.
Enote, J., S. Albert, K. Webb, 1993. Zuni resource development plan: A program of action for sustainable resource development. Zuni Conservation Project, Zuni Pueblo.
Evenari, M.L., L. Shanan, N. Tadmor, 1982. The Negev: The challenge of the desert. Harvard University Press, Cambridge.
Frasier, G.W., 1980. Harvesting water for agricultural, wildlife, and domestic uses. Journal of Soil and Water Conservation. 35: 125-128.
Gellis, A.C., A. Cheama, V. Laahty, S. Lalio, 1995. Assessment of gully-control structures in the Rio Nutria Watershed, Zuni Reservation, New Mexico. Water Resources Bulletin. 31: 633-646.
Hack, J.T., 1942. The changing physical environment of the Hopi Indians of Arizona. Papers of the Peabody Museum of American Archaeology and Ethnology, Harvard. 35: 1-85.
Hart, E.R., 1995. Zuni and the courts: A struggle for sovereign land rights. University Press of Kansas, Lawrence, pp. 337.
Herold, L.C., 1965. Trincheras and physical environment along the Rio Gavilan, Chihuahua, Mexico. Dept. of Geography, University of Denver Publications in Geography 65-1.
Kowsar, A., 1991. Floodwater spreading for desertification control: An Integrated Approach. Desertification Bulletin: 3-18.
Leopold, L.B., W.W. Emmett, R.M. Myrick, 1966. Channel and hillslope processes in a semiarid area, New Mexico. United States Geological Survey 352-G.
Manolescu, K., 1995 . Hopi corn production. Bureau of Indian Affairs.
McCall, G.A., R.W. Frazer, 1968. New Mexico in 1850: A military view. Univ. of Oklahoma Press, Norman.
Miller, R.F., I.S. McQueen, F.A. Branson, L.M. Shown, W. Buller, 1969. An evaluation of range floodwater spreaders. Journal of Range Management. 22: 246-257.
Nabhan, G., 1981. Runoff farming for dry lands. Arid Lands Newsletter. May/June: 50-53.
Nabhan, G., 1984. Soil fertility renewal and water harvesting in Sonoran Desert agriculture: The Papago example. Arid Lands Newsletter. 20: 21-28.
Neimeijer, D., 1993. Indigenous runoff farming in a changing environment: The case of Kassala's border area, Sudan. University of Amsterdam.
Norton, J.B., 1996. Soil, geomorphic, and ecological factors in Zuni runoff agriculture. MS-Iowa State University, Ames, IA.
NRCS, in press. Soil survey of the Zuni Indian Reservation. USDA National Resource Conservation Service, Washington, D.C.
OTA, 1983. Water-related technologies for sustainable agriculture in U.S. arid/semiarid lands. U.S. Congress, Office of Technology Assessment OTA-F-212.
Pawluk, R.R., 1995. Indigenous knowledge of soils and agriculture at Zuni Pueblo, New Mexico. Iowa State University.
Pawluk, R.R., J.A. Sandor, J.A. Tabor, 1992. The role of endigenous soil knowledge in agricultural development. Journal of Soil and Water Conservation. 47: 298-302.
Perrier, E.R., 1988. Opportunities for the productive use of rainfall normally lost to xropping for temporal or apatial eeasons. In: F. R. Bidinger and C. Johansen (eds.) Drought research priorities for the dryland tropics. ICRISAT, Patancheru, India. pp. 113-129.
Sandor, J.A., 1995. Searching soil for clues about Southwest prehistoric agriculture. In: H. W. Toll (ed.) Proc. of the New Mexico Archaeological Council Symposium on Southwest Agriculture.
Sandor, J.A., P.L. Gersper, J.W. Hawley, 1986a. Soils at prehistoric agricultural terracing sites in New Mexico: I. Site placement, soil morphology, and classification. Soil Science Society of America Journal. 50: 166-173.
Smith, J.E., 1987. Mesas, cliffs, and canyons: the University of Colorado survey of Mesa Verde National Park, 1971-1977. Mesa Verde Museum Association, Inc.
Stewart, G.R., 1940. Conservation in Pueblo agriculture: II. Present-day flood water irrigation. Scientific Monthly. 51: 329-340.
Tabor, J.A., 1995. Improving crop yields in the Sahel by means of water-harvesting. Journal of Arid Environments. 30: 83-106.
Wells, S.G., D.W. Love, T.W. Gardner, 1983. Chaco Canyon country. A.G.F.G., pp. 253.
Jonathan A. Sandor can be reached at:Agronomy Department
Most of the web sites I found associated with Zuni Pueblo were advertisements for tours or other products, but the following offer some good, though generally brief, information:
A brief description of Zuni history and culture (http://hanksville.phast.umass.edu/defs/Heard/southwest.html) can be read on the Heard Museum web site.
Some Zuni stories (http://www.indians.org/welker/zuni.htm) are available from the Indigenous People's Literature web site.
Information on indigenous water harvesting for agriculture
This article from International Ag-Sieve Volume 15, No. 3, briefly describes the agricultural practices (including water harvesting) of the Hohokam people, (http://fadr.msu.ru/rodale/agsieve/txt/vol5/3/art1.html), who lived from about 500 to 1450 A.D. in the region of what is now central Arizona.
Another International Ag-Sieve article, this one from Volume 12, No. 8, discusses the general potential for runoff agriculture in arid lands (http://fadr.msu.ru/rodale/agsieve/txt/vol2/8/art1.html).
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