Long Term Projects

Overview

Oregon Agricultural Experiment Station

TITLE: Developing Sustainable Field Cropping Systems in Semi-arid Eastern Oregon

New Long-Term Studies

Wheat is the major field crop produced in north-central and northeastern Oregon and most cropping systems in these areas revolve around wheat production. Wheat is primarily grown under the wheat/fallow rotation that is used on 4.5 million acres in north-central Oregon and south-central Washington, where rainfall is considered inadequate to produce a crop every year. The wheat/fallow cropping system reduces soil organic carbon, exacerbates soil erosion and it is not biologically sustainable (Rasmussen and Parton, 1994). Despite concerns of decline in soil resources and sustainability, adoption of alternate cropping systems, such as intensive cropping and direct seeding, has been slow due to lack of long-term research in Oregon on viability of alternate cropping systems. Long-term research that was conducted at the Sherman Experiment Station and concluded in the early 60s indicated that there were occasional crop failures under conventional continuous cropping systems (Hall, 1955; 1960; 1963). With the advent of new varieties and agronomic practices, research is needed to enhance benefits and reduce risks for annual cropping. Possible research avenues include the use of varieties more tolerant to drought, low temperature, pests, and conservation tillage systems that can ensure good stands and economical weed and disease control.

PREVIOUS WORK AND PRESENT OUTLOOK

Long-Term Studies

Summer-fallow is used primarily to store winter precipitation, accumulate nutrients (N, S), and to control weeds and is economical where rainfall is less than 13 inches (Leggett et al, 1974; Bolton and Glen, 1983). The development of high yielding semi-dwarf wheat varieties with high water-use efficiency and disease resistance has not been able to overcome the decline in biological sustainability in the PNW (Duff et al, 1995). Trends after the 1950s indicate that economic sustainability is also declining in PNW fallow cropping systems because costs are continuing to rise while wheat prices remain static (Duff et al, 1995). Conservation tillage, annual cropping, and the introduction of alternative crops into wheat-based rotations are potential ways to improve biological sustainability of cropping systems in north-central Oregon and south-central Washington. Unfortunately, long-term data showing the benefits and shortcomings of the alternative cropping systems in this region are lacking. Long-term research to develop biologically and economically sustainable farming systems is urgently needed in north-central Oregon and south-central Washington. I hypothesize that reduced tillage systems that leave more residues on the surface, and intensive cropping will increase soil OM, increase soil available moisture, reduce water and wind erosion, and sustain soil productivity compared to the traditional fallow system.

The ultimate objective of this project is to develop acceptable and sustainable cropping systems for north-central Oregon and south-central Washington. The desired cropping systems should increase residue cover, increase soil OM, increase soil available moisture, reduce wind and water erosion, reduce soil water evaporation, sustain soil productivity, and increase farm profits. Work to accomplish this objective, however, will be conducted in separate experiments whose specific objectives are listed below.

INSTITUTIONAL UNITS INVOLVED AND COOPERATORS

Oregon State University

Columbia Basin Agricultural Research Center; Pendleton
Department of Crop and Soil Science; Corvallis
Extension Service; Statewide

Washington State University

Department of Crop and Soil Sciences; Pullman
Extension Service; Statewide

University of Idaho

Department of Plant, Soil, and Entomological Sciences; Moscow

USDA-Agricultural Research Service; Pendleton and Pullman

USDA-Natural Resource Conservation Services; Oregon and Washington

For a full description of description of all Long-term experiments click here

Objectives

Objectives:

Objective 1 (Long-term experiments):

To establish a series of long-term experiments that will compare the effects of conventional crop rotations and crop management practices with potential alternative crop rotations and crop management practices such as direct seeding.

Procedures and Methods

Long-Term Experiments

The experiments will be established at the Sherman Experiment Station in Moro in the fall of 2002. The Station has a total of 230 acres and receives an average of 11.4 inches of annual precipitation. The soils are Walla Walla silt loams with slopes up to 15%. Preliminary estimates indicate that about 10-20 acres of land would be required for this experiment. Rainfall and soils at the station are representative of the conditions in north-central Oregon. Conventional wheat/fallow systems will be compared to a range of treatments that includes conservation and intensive tillage systems. The final treatments and management practices will be determined in consultation with grower advisory committee and collaborating scientists. Based on recent meetings, core treatments will include the following:

1. Winter wheat (WW) Summer fallow

2. WW Chemical fallow (CF)

3. WW, continuous Direct Seed (DS)

4. Spring Wheat (SW) cont. DS

5. WW SW or Spring Barley CF

6. Flex crop-grower advisory group and scientists decide on yearly operations

Agronomic practices (planting date, planting rate, and fertilizer, herbicides and insecticide application) will be based on the treatment in question. Data on the timing of agronomic practices, dates of emergence, anthesis, and maturity, plant counts, soil moisture, diseases, weeds, insect pest, biomass, and yield will be collected. More studies will be added after the first year of treatment establishment. Funds to establish these studies and to sustain experimentation will be solicited from funding organizations such as STEEP and WSARE. Information obtained from this experiment will go a long way in influencing growers to adopt sustainable cropping practices. Furthermore this information will be an important reference to policy makers during farm programs formulation.

Literature

Literature:

Literature cited

Bolton, F.E. and D.M. Glen. 1983. Fallow-Cropping Systems in the Pacific Northwest. Tech. Bull. 146, Oregon State Univ. Agric. Expt. Stn, Corvallis, OR.

Duff, B., P.E. Rasmussen, and R.W. Smiley. 1995. Wheat/Fallow Systems in Semi-arid Regions of the Pacific NW America. p. 85-109. In V. Barnett, R. Payne, and R. Steiner (ed.) Agricultural Sustainability: Economic, Environmental and Statistical Consideration. John Wiley and Sons, Chichester.

Hall, W.E. 1955. Report of the Sherman Branch Experiment Station. Oregon State University, Sherman Branch Experiment Station, Moro, OR.

Hall, W.E. 1960. Annual Report of the Sherman Branch Experiment Station. Oregon State University, Branch Experiment Station, Moro.

Hall,W. E. 1963. Annual Report of the Sherman Branch Experiment Station. Oregon State University, Branch Experiment Station, Moro.

Leggett, G.E., R. E. Ramig, L.C. Johnson, and T.W. Masse. 1974. Summer fallow in the Northwest. p. 110-135. In Summer Fallow in the Western United States. Conservation Research Report No. 17, USDA-ARS, Washington, DC.

Rasmussen, P.E., and W.J. Parton, 1994. Long-term effects of residue management in wheat/fallow. I. Inputs, yield, soil organic matter. Soil Science Society of America Journal. 58:523-530.

Long Term Projects

Literature cited

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