Progress 07/01/09 to 06/30/12

Outputs
OUTPUTS: Changes in soil quality parameters may be an early warning signal to indicate changes so that degrading effects can be remedied and soil building practices can be implemented. The objective of this research is to characterize biological, physical and chemical soil quality parameters and monitor their changes over time in minimum tillage and no-till seeding systems as affected by tillage, crop species and management systems. From this research, information was obtained to better assess the health or quality of soils specifically for the dryland-farming region of eastern Washington and north central Idaho. The data collected was used to better predict residue decomposition in the field, more fully test cultivars for their contributions to soil fertility, and assist growers in identifying traits for residue management prior to making planting decisions for conservation farming systems. Information gained on residue traits and decomposition can also be useful in developing alternative fuels. We have presented information at annual field days and annual winter grower meetings as well as at scientific meetings. We have published this information in scientific publications, technical publications and grower guides. Several publications are in press. We have also updated the NIRS protocol for cereals and published a peer-reviewed publication. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage. PARTICIPANTS: Ann C. Kennedy, Brenton Sharratt, Jeremy Hansen, USDA-ARS, Pullman, WA Tami L. Stubbs, William Schillinger, WSU All prticipants were routinely educated in saftey and occasionally attended miscellaneous training sessions in soil microbiology and soil quality. TARGET AUDIENCES: Scientists, researchers, growers, field personnel and students PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Conservation tillage or no-tillage systems are needed in the Pacific Northwest (PNW) to reduce soil erosion, maintain soil quality, enhance crop yields and improve farm profitability. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage. Soil organic carbon increased over time with long-term no-till. Long-term no-till also increased the proportion of aggregates in the larger sized soil fractions. Microbial community analysis showed changes with long-term no-till and an increase in the fungal component and the gram-negative bacteria. Stress indicators also tended to decrease with no-till compared to high disturbance. Changes in the microbial community and other soil quality parameters such as pH, EC, bulk density and microbial enzyme activity were variable in their response. Soil quality changes during the transition to no-till are less dramatic and more variable in the low (less than 300- mm annual) precipitation zones compared to the higher (300- to 550- mm annual) precipitation zones. Data from these long-term experiments will allow us to better assess the health or quality of soils in dryland cropping regions to aid growers in the transition to no-till cropping. Long-term studies are needed to fully understand the subtle and often slow changes occurring in the soil environment with conservation tillage practices. The goal is to identify soil quality parameters that can be used in the development of best management practices for conserving soil quality and enhancing crop production. Fiber (neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL)) and nutrient (nitrogen (N), carbon (C)) analysis showed that straw composition of cultivars of spring barley, spring wheat, and winter wheat grown at four locations in eastern Washington over two crop years varied with crop type. Acid detergent lignin was highest in spring. The analysis normally used to determine fiber content of straw is expensive and labor intensive. We developed near-infrared spectroscopy (NIRS) as a rapid, non-destructive, chemical-free method to predict residue fiber and nutrient content of wheat and barley. Residue decomposition rate can be predicted by hemicellulose, cellulose and lignin content of plant residue, among other traits, which are calculated from analysis for NDF, ADF and ADL. We found that NIRS was a successful method for predicting NDF and ADF, and sometimes ADL, in cereal crop residue. Although LECO analysis is time-consuming, it generates no toxic waste, and coupled with NIRS analysis of fiber components yields valuable information for the prediction of residue decomposition potential of cereal residue. Fiber and nutrient characteristics of residue from wheat and barley cultivars currently produced in the Pacific Northwest can be used to predict residue decomposition in cropping systems that conserve soil and water, and enhance build-up of soil organic matter.

Publications

• Stubbs, T.L. and A.C. Kennedy. 2009. Composition of Cereal Crop Residue in Dryland Cropping Systems. Washington State Univ. 2009 Dryland Field Day Abstracts, pg. 44.
• Stubbs, T.L. and A.C. Kennedy. 2009. Residue Composition and Soil Quality in Conservation Tillage Systems. Meeting of the Washington Society of Professional Soil Scientists, Ellensburg, WA, Feb. 27, 2009.
• Stubbs, T.L., A.C. Kennedy, P.E. Reisenauer and J.W. Burns. 2009. Chemical composition of residue from cereal crops and cultivars in dryland ecosystems. Agron. J. 101:538-545.
• Unger, I.M., A.C. Kennedy, and R. M. Muzika. 2009. Flooding effects on soil microbial communities. Applied Soil Ecology 42:1-8.
• Schillinger, W.F., D.L. Young, A.C. Kennedy, and T.C. Paulitz. 2010. Diverse no-till irrigated crop rotations instead of burning and plowing continuous wheat Field Crops Research 115:39-49.
• Stubbs, T.L., A.C. Kennedy, and A.-M. Fortuna. 2010. Using NIRS to predict fiber and nutrient content of dryland cereal cultivars. Journal of Agricultural and Food Chemistry. 58:398-403.
• Kennedy, A.C. 2009. CRP takeout An excellent opportunity to begin direct seeding. Pacific Northwest Sustainable Agriculture Newsletter.pp 1.
• Kennedy, A.C. 2009. Preserve CRP Soil Quality by Direct Seeding. WSU Field Days-2009. Washington State University, Pullman, WA pp.23.
• Perry, A. 2009. Reaping More Rewards from Crop Residues. Agricultural Research News. June 12, 2009.

Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: The data will be used to better predict residue decomposition in the field, more fully test cultivars for their contributions to soil fertility, and assist growers in identifying traits for residue management prior to making planting decisions for conservation farming systems. Information gained on residue traits and decomposition will be useful in developing alternative fuels. We have presented information at many field days and several winter grower meetings as well as at scientific meetings. Those presentations that required abstracts are listed in the publications. We have published this information in scientific journals and are working on technical publications and grower guides. Technical publications will include a Pacific Northwest extension article or a Conservation Tillage Update article. We have also updated the NIRS protocol for cereals. PARTICIPANTS: Tami L. Stubbs, Washington State University; Jeremy C. Hansen, USDA-ARS; William Schillinger, Washington State University; Brenton S. Sharratt, USDA-ARS TARGET AUDIENCES: The scientific community, other government agencies, agricultural industry, field personnel, consultants and growers will benefit from our scientific research results and extension activities. The general public benefits from our outreach program. In addition our outreach to these various groups enhances our knowledge base of the needs of our stakeholders. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
An understanding of residue decomposition patterns, gained by knowing the fiber content of crop cultivars, will aid growers in determining fertility requirements and planning annual crop rotations for high rainfall regions where residue is excessive, or for low rainfall zones where residue levels may be inadequate to prevent soil erosion. This information may also determine the mineralization and immobilization of nutrients as affected by the fiber component and nutrient composition of crop residue. Cereal cultivars produced in the Pacific Northwest may be characterized for their suitability in ethanol production, paper and strawboard production, and as a substrate for mushroom production. Additionally, this information on fiber characteristics can be used when selecting for disease resistance. Multiple fiber and nutrient characteristics are needed to best predict the decomposition potential of cereal cultivars in dryland agriculture. Using Near-Infrared Spectroscopy (NIRS), we can conclude that NIRS is able to differentiate NDF and ADF, and ADL to a lesser extent, and NIRS can be used to predict decomposition potential for each cultivar without using the more labor intensive wet-chemistry methods. At this time, NIRS prediction would not be used to replace C, N and S analysis using the classic LECO method to rank cereal cultivars for their decomposition potential.

Publications

• Stubbs, T.L., A.C. Kennedy, P.E. Reisenauer and J.W. Burns. 2009. Chemical composition of residue from cereal crops and cultivars in dryland ecosystems. Agron. J. 101:538-545.
• Stubbs, T.L., A.C. Kennedy, A.-M. Fortuna. Using NIRS to predict fiber and nutrient content of dryland cereal cultivars. 2010. Journal of Agricultural and Food Chemistry (DOI:10.1021/jf9025844).
• Stubbs, T.L. and A.C. Kennedy. 2009. Composition of Cereal Crop Residue in Dryland Cropping Systems. Washington State Univ. 2009 Dryland Field Day Abstracts, pg. 44.
• Schillinger, W.L., D.L. Young, A.C. Kennedy, T.C. Paulitz. 2010. Diverse no-till irrigated crop rotations instead of burning and plowing continuous wheat. Field Crops Research 115: 39-49.

Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: These projects are part of the Columbia Plateau PM10 Project. Results will be distributed in appropriate academic, industry and producer publications, and project reports. Findings from this research will be incorporated into current and future extension activities of the principal investigators. We will present information at winter grower meetings, field days and land-manager meetings, as well as at scientific meetings. This information will be published in technical reports, grower guides and scientific publications. Technical publications will include Wheat Life, Pacific Northwest and Western extension articles. This project will also foster and strengthen the collaborations among USDA-ARS, Washington State University and the University of Idaho. This collaboration will enhance relationships so that the organizations can share facilities and resources, exchange information, develop cooperative educational programs, and conduct joint research on national and regional issues. This project will advance the training and education of both undergraduate and graduate students by providing a unique opportunity for them to work on a complex problem that has rangeland management implications. Students will be exposed to field, greenhouse, and laboratory research using several cutting-edge analytical techniques. PARTICIPANTS: Tami L. Stubbs, CSS WSU William F. Schillinger, CSS WSU; Brenton Sharratt, USDA- ARS; Jeremy Hansen, USDA-ARS TARGET AUDIENCES: The scientific community, other government agencies, agricultural industry, field personnel, consultants and growers will benefit from our scientific research results and extension activities. The general public benefits from our outreach program. In addition our outreach to these various groups enhances our knowledge base of the needs of our stakeholders. PROJECT MODIFICATIONS: We have added objective # 2 to investigate Carbon lost in wind erosion to focus in on organic matter loss.

Impacts
Information is needed on the changes in soil organic matter and the soil biota due to wind erosion to aid in the development of management practices. Our overall objective is to determine the effect of wind erosion and management practices on soil organic matter, soil biological communities and soil quality characteristics. The first objective of this research is to characterize biological, physical and chemical soil quality parameters and monitor their changes over time in tillage systems of dryland farming systems. Soil quality parameters were assessed at several long-term dryland cropping systems research sites in eastern Washington to further define management practices that are soil building rather than degrading. Soil organic carbon slowly increased in long-term no-till and approached or exceeded that of nearby undisturbed sites. Long-term no-till also increased the proportion of aggregates in the larger sized soil fractions. No-till soils stored a greater proportion of the carbon in the larger size aggregates, thus protecting more of the carbon from loss due to wind erosion. Slight differences in soil quality among residue treatments are evident. In a long-term no-till drill study we found no differences in the soil properties tested. Our second objective is to quantify the carbon content and biological fingerprints found in wind-eroded sediments from agricultural soils. We are investigating the carbon content and biological fingerprint of fractions of agricultural soil collected in Big Spring Number Eight (BSNE) sample collectors. We have seen variable response of C in BSNE depending on location and date. We found that the carbon content of agricultural soil collected in BSNE sample collectors was either the same as or greater than the bulk soil. Carbon values were similar at all collection heights. We also found that the biological fingerprint of the suspended material was somewhat different from that of the bulk soil. These results indicate that soil from up-wind sites was being collected on these samplers. Our third objective is to characterize cereal cultivars by their fiber, tannin and nutrient components and determine how residue decomposition is linked to these characteristics. We found that cereal crop cultivars varied in their nitrogen, carbon and fiber content. Of 42 cultivars tested, 14% had characteristics for slow residue decomposition and 14% had rapid decomposition potential. Other cultivars had some indication of either being rapidly or slowly decomposed, while the rest fell into the intermediate range. High hemicellulose and total N can be linked to rapid decomposition, and high lignin content and high C:N ratio are associated with slower breakdown. Fiber and nutrient characteristics of residue from wheat and barley cultivars currently produced in the Pacific Northwest can be used to predict residue decomposition in cropping systems that conserve soil and water, and enhance build-up of organic matter.

Publications

• No publications reported this period

Progress 01/01/07 to 12/31/07

Outputs
The objective of this research is to characterize biological, physical and chemical soil quality parameters and monitor their changes over time in minimum tillage and no-till seeding systems as affected by tillage, crop species and management systems. Soil organic carbon increased over time with long-term no-till. Long-term no-till also increased the proportion of aggregates in the larger sized soil fractions. Microbial community analysis showed changes with long-term no-till and an increase in the fungal component and the gram-negative bacteria. Stress indicators also tended to decrease with no-till compared to high disturbance. Changes in the microbial community and other soil quality parameters such as pH, EC, bulk density and microbial enzyme activity were variable in their response. Soil quality changes during the transition to no-till are less dramatic and more variable in the low (less than 300- mm annual) precipitation zones compared to the higher (300- to 550- mm annual) precipitation zones. Data from these long-term experiments will allow us to better assess the health or quality of soils in dryland cropping regions to aid growers in the transition to no-till cropping. Long-term studies are needed to fully understand the subtle and often slow changes occurring in the soil environment with conservation tillage practices. The goal is to identify soil quality parameters that can be used in the development of best management practices for conserving soil quality and enhancing crop production.

Impacts
Conservation tillage or no-tillage systems are needed in the Pacific Northwest (PNW) to reduce soil erosion, maintain soil quality, enhance crop yields and improve farm profitability. Changes in soil quality parameters may be an early warning signal to indicate changes so that degrading effects can be remedied and soil building practices can be implemented. We found several early indicators that may be useful in indicating the potential soil building and soil degrading practices. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage.

Publications

• Kennedy. A.C. and Stubbs, T.L. 2007. Management effects on the incidence of jointed goatgrass inhibitory rhizobacteria. Biocontrol 40:213-221.
• Lupwayi, N.Z. and Kennedy, A.C. 2007.Grain legumes in Northern Great Plains: Impacts on selected soil biology processes. Agronomy Journal 99:1700-1709.
• Schillinger, W.F., Kennedy, A.C. and Young, D.L. 2007. Eight years of annual no-till cropping in Washington's winter wheat - summer fallow region. Agric. Ecosys. Environ. 120: 345-358.
• Cochran, R.L., Collins, H.P., Kennedy, A.C. and Bezdicek, D.F. 2007. Soil carbon pools and fluxes following land conversion in a semi-arid shrub-steppe ecosystem. Biol. Fertil. Soils. 43:479-489.

Progress 01/01/06 to 12/31/06

Outputs
The objective of this research is to characterize biological, physical and chemical soil quality parameters and monitor their changes over time in minimum tillage and no-till seeding systems as affected by tillage, crop species and management systems. Soil organic carbon increased over time with long-term no-till. Long-term no-till also increased the proportion of aggregates in the larger sized soil fractions. Microbial community analysis often showed changes with long-term no-till and an increase in the fungal component. Changes in the microbial community and other soil quality parameters such as pH, EC, bulk density and microbial enzyme activity were variable in their response. Soil quality changes during the transition to no-till are less dramatic and more variable in the low (less than 300-mm annual) precipitation zones compared to the higher (300-to 550-mm annual) precipitation zones. Data from these long-term experiments will allow us to better assess the health or quality of soils in dryland cropping regions to aid growers in the transition to no-till cropping. Long-term studies are needed to fully understand the subtle and often slow changes occurring in the soil environment with conservation tillage practices. The goal is to identify soil quality parameters that can be used in the development of best management practices for conserving soil quality and enhancing crop production.

Impacts
Conservation tillage or no-tillage systems are needed in the Pacific Northwest (PNW) to reduce soil erosion, maintain soil quality, enhance crop yields and improve farm profitability. Changes in soil quality parameters may be an early warning signal to indicate changes so that degrading effects can be remedied and soil building practices can be implemented. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage.

Publications

• Kennedy, A. C. and Schillinger, W.F. 2006. Soil quality and water intake in conventional-till vs. no-till paired farms in Washington Palouse Region. Soil Sci. Soc. Amer. J. 70:940-949.
• Kennedy. A.C., Stubbs, T. L., and Hansen, J. C. 2006. This land is your land. Science and Children. Dec 06 pp 22-26.

Progress 01/01/05 to 12/31/05

Outputs
The objective of this research is to characterize biological, physical and chemical soil quality parameters and monitor their changes over time in minimum tillage and no-till seeding systems as affected by tillage, crop species and management systems. The goal is to identify soil quality parameters that can be used in the development of best management practices for conserving soil quality and enhancing crop production. Soil organic carbon slowly increased in long-term no-till and approached or exceeded that of nearby undisturbed sites. Long-term no-till also increased the proportion of aggregates in the larger sized soil fractions. Also, no-till stored a greater proportion of the carbon in the larger size aggregates thus protecting more of the carbon from loss due to wind erosion. The soil quality of continuous winter wheat-burn-plow treatment is being degraded compared to direct seed treatments. Slight differences in soil quality among residue treatments are evident. In a long-term no-till drill study we found no differences in the soil properties tested in these two sites. With direct seeding, the lower disturbance has more of an impact on soil quality measurements than surface residue management.

Impacts
Conservation tillage or no-tillage systems are needed in the Pacific Northwest (PNW) to reduce soil erosion, maintain soil quality, enhance crop yields and improve farm profitability. The impacts of management practices on soil biotic and abiotic properties need to be considered before adoption of or changes in those practices. Changes in soil quality parameters may be an early warning signal to indicate changes so that degrading effects can be remedied and soil building practices can be implemented. From this research, information will be obtained to better assess the health or quality of soils specifically for the dryland-farming region of eastern Washington and north central Idaho. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage.

Publications

• Banowetz, G. M., G. W. Whittaker, K. P. Dierksen, M.D. Azevedo, A.C. Kennedy, S. M. Griffith, and J. J. Steiner. 2006. Fatty acid methyl ester analysis (FAME) to identify sources of sediment. J. Environ. Qual. 35:133-140.
• Mohammad, M., W.L. Pan, and A. C. Kennedy. 2005. Chemical alterations in the rhizosphere of mycorrhizal-infected wheat roots. Mycorrhiza 15:327-332.

Progress 01/01/04 to 12/31/04

Outputs
The change with soil quality parameters in the transition period from conventional tillage to no-till appears to take longer and can be more variable in lower rainfall zones. Changes occurring with microbial communities were measured before changes in organic matter or other chemical or physical parameters. Most importantly, we found that organic matter increased with long term direct seed. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices. No-tillage offers potential for improved soil quality, reduced erosion, and equal or increased crop yields. To better understand microorganisms and weed seed decay in no-till systems, we evaluated the effects of tillage, soil fumigation, and fungicides on the decay of wild oat. We demonstrated that more than half of the wild oat seed bank reduction could be directly attributed to germination, whereas loss due to decay was relatively low; however, decay was occurring. Soil borne fungi were identified that infect and decay wild oat seeds. These fungi could contribute to depletion of the weed seed bank through seed infection leading to loss of germination and vigor. This research will enable scientists to create conditions necessary for weed suppressive soils. Residue management is a concern of producers adopting minimum tillage systems. In some areas, growers are faced with the management of large amounts of residue from the previous year's crop. Conversely, in the low-rainfall region of eastern Washington the must maintain enough residue to prevent erosion. We determined that cultivars of wheat and barley straw differ in their rate of decomposition in the field and this may be related to the variation in their fiber content (hemicellulose and lignin) and C:N ratio. Information on decomposition of wheat and barley cultivars will be useful to breeders and aid growers in planning rotations for reduced tillage systems. In studies of no-till versus conventional tilled fields, we find that aggregate distribution of the soil mineral fraction changes with no-till. No-till fields have a greater proportion of soil in the larger size fraction and less soil in the smaller or more erodible fraction. Organic matter content tends to be greater in the no-till fields especially after long-term no-till.

Impacts
This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage.

Publications

• Gallandt, E.R., E.P. Fuerst and A.C. Kennedy. 2004. Effect of tillage, fungicide seed treatment, and soil fumigation on seed bank dynamics of wild oat (Avena fatua). Weed Science 52:597-604.
• Kennedy, A. C. 2004. The biota of the rhizosphere. pp 242-262. In: D. M. Sylvia, J. J. Furhman, P. G. Hartel and D. A. Zuberer. (eds.) Principles and Applications of Soil Microbiology. Prentice Hall, Upper Saddle River, New Jersey.
• Kennedy, A. C., and L. Z. de Luna. 2004 Rhizosphere. pp. 399-406. In: D. Hillel (ed.) Encyclopedia of Soils in the Environment. Elsevier LTD, Oxford UK Harcourt Publishers, London UK.
• Kennedy, A. C., T. L. Stubbs and W. F. Schillinger. 2004. Soil and crop management effects on soil microbiology. pp 295-326. In F. Magdoff and R. R. Weil (eds.) Soil Organic Matter in Sustainable Agriculture. Advances in Agroecology Series, CRC Press. Boca Raton, FL.
• Stubbs, T. L., A. C. Kennedy and W. Schillinger. 2004. Changing ecology in changing tillage systems. New Dimensions in Agroecology. Journal of Crop Improvement. 11:105-135.

Progress 01/01/03 to 12/31/03

Outputs
The objective of this research is to characterize biological, physical and chemical soil quality parameters and monitor their changes over time in minimum tillage and no-till seeding systems as affected by tillage, crop species and management systems. The goal is to identify soil quality parameters that can be used in the development of best management practices for conserving soil quality and enhancing crop production. We have found that soil quality changes during the transition to direct seed are less dramatic and more variable in the low precipitation zones compared to the higher precipitation zones. In the early part of the transition period the amount of disturbance has greater immediate impact than surface residue management or crop rotation. Organic matter increases with long-term direct seed, although this increase may take many years to become apparent. We also continue to see that long-term direct seeding results in changes in microbial communities and an increase in fungi:bacteria ratios.

Impacts
This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage.

Publications

• Acosta-Martinez, V., T.M. Zobeck, T.E. Gill, and A.C. Kennedy. 2003. Enzyme activities and microbial community structure in semiarid agricultural soils. Bio. Fert. Soils. 38:216-227.
• Dierksen, K. P., G. W. Whittaker, G. M. Banowetz, M. A. Azevedo, A. C. Kennedy, J. J. Steiner, and S. M. Griffith. 2003. High resolution characterization of soil biological communities by nucleic and fatty acid analyses. Soil. Bio. Biochem. 34:1853-1860.

Progress 01/01/02 to 12/31/02

Outputs
Soil quality parameters are being assessed at several sites involved in the wind erosion project to determine the health of a soil by defining management practices that are soil building rather than degrading. Overall we found that as the time into no-till increased, so too did measurable differences in organic carbon, the microbial community and bulk density. The change with soil quality parameters in the transition period to no-till appears to take longer and be more variable in lower rainfall zones. Cropping systems changes were difficult to consistently measure, possibly due to the short-term nature of the studies. Other results varied with site.

Impacts
Conservation tillage or no-tillage systems are needed in the Pacific Northwest (PNW) to reduce soil erosion, maintain soil quality, enhance crop yields and improve farm profitability. The impacts of management practices on soil biotic and abiotic properties need to be considered before adoption of or changes in those practices. Changes in soil quality parameters may be an early warning signal to indicate changes so that degrading effects can be remedied and soil building practices can be implemented. From this research, information will be obtained to better assess the health or quality of soils specifically for the dryland-farming region of eastern Washington and north central Idaho. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage.

Publications

• No publications reported this period

Progress 01/01/01 to 12/31/01

Outputs
Soil quality parameters are being assessed at several sites involved in the wind erosion project to determine the health of soil by defining management practices that are soil building rather than degrading. The objective of this research is to characterize biological, physical and chemical soil quality parameters and monitor their changes over time in minimum tillage and no-till seeding systems as affected by tillage, crop species and management systems. The goal is to identify soil quality parameters that can be used in the development of best management practices for conserving soil quality and enhancing crop production. For several of the sites tested, as the time into no-till increases, we find increased organic carbon values, changes in the microbial community and decreases in bulk density in the surface soil. Other soil quality parameters are variable in their response. The change with soil quality parameters in the transition period to no-till appears to take longer and can be more variable in lower rainfall zones. Changes in cropping systems were difficult to measure; however, differences in soil quality parameters were often seen with changes in crop type or sequence. Changes occurring with microbial communities can be measured before changes in organic matter or other chemical or physical parameters. No single soil quality measurement was able to predict changes in some of the other parameters. From this research, information will be obtained to better assess the health or quality of soils specifically for the dryland-farming region of eastern Washington and north central Idaho. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices.

Impacts
The impacts of management practices on soil biotic and abiotic properties need to be considered before adoption of or changes in those practices. Changes in soil quality parameters may be an early warning signal to indicate changes so that degrading effects can be remedied and soil building practices can be implemented. From this research, information will be obtained to better assess the health or quality of soils specifically for the dryland-farming region of eastern Washington and north central Idaho.

Publications

• Stubbs, T. L., A. C. Kennedy, and R. Kremer. 2001. Deleterious bacteria in the rhizosphere. Agronomy Abstracts. American Society of Agronomy, Madison, WI. 65:263. 2001.
• Frohne, P.S., J. J. Halvorson, and A. C. Kennedy. 2001. Microbial community structure and function in Mount St. Helens pyroclastic substrate. Ecological Society of America Abstracts
• McCool, D. K., C. D. Pannkuk, A. C. Kennedy, and P. S. Frohne. 2001. Effects of Burn/Low-Till on Erosion and Soil Quality. 31 pp. Washington State University, College of Agriculture and Home Economics Miscellaneous Publication No. XB1040, Pullman, WA. 2001.
• Weddell, B. J., A. C. Kennedy, P. S. Frohne, and S. Higgins. 2001. Experimental test of microbial biocontrol of cheatgrass. pp. 22-26. In: Restoring Palouse and Canyon Grasslands: Putting back the missing pieces. Bureau of Land Management Report, Cottonwood, ID.
• Weddell, B. J., P. S. Frohne, and A. C. Kennedy. 2001. Soil biological fingerprints from meadow steppe and steppe communities with native and non-native vegetation. pp. 12-21 In: Restoring Palouse and Canyon Grasslands: Putting back the missing pieces. Bureau of Land Management Report, Cottonwood, ID.

Progress 01/01/00 to 12/31/00

Outputs
Soil quality parameters are being assessed at several sites involved in the wind erosion project to determine the health of a soil by defining management practices that are soil building, rather than degrading. Overall, we found that as the time into no-till increased, so too did measurable differences in organic carbon, the microbial community and bulk density. The change with soil quality parameters in the transition period to no-till appears to take longer and be more variable in lower rainfall zones. Cropping systems changes were difficult to consistently measure, possibly due to the short-term nature of the studies. Other results varied with site.

Impacts
Conservation tillage or no-tillage systems are needed in the Pacific Northwest (PNW) to reduce soil erosion, maintain soil quality, enhance crop yields and improve farm profitability. The impacts of management practices on soil biotic and abiotic properties need to be considered before adoption of or changes in those practices. Changes in soil quality parameters may be an early warning signal to indicate changes so that degrading effects can be remedied and soil building practices can be implemented. From this research, information will be obtained to better assess the health or quality of soils specifically for the dryland-farming region of eastern Washington and north central Idaho. This information will ultimately provide growers and scientists with practical advice on soil quality to aid in the development of management practices in order to retain the benefits of improved soil quality resulting from management decisions such as reduced tillage.

Publications

• No publications reported this period