I earned my B.S. and M.S. degrees at Iowa State University, with the grad degree focused on soil management and sustainable agricultural practices. Since joining NLAE in October, 1996, I have worked on projects from the greenhouse to field and watershed scales. Those projects have focused on N fertilizer management impacts on water quality and crop production, soil health, humic products’ impacts on crop production and the soil environment, and most currently, fragipan soil management. I was raised on a small crop and livestock farm in northeast Iowa and was motivated to my career to help improve ag sustainability. I and my wife are active in our church and are a part of the missions team. We enjoy traveling to the Philippines to be with family there. When the opportunities exist, I also enjoy fishing, hiking, gardening and testing my dear wife’s patience with rock collecting.

• Publications

  • (Clicking on the reprint icon will take you to the publication reprint.)
  • Fragipan horizon changes using annual ryegrass and other amendments -(Peer Reviewed Journal)
    Murdock, L.W., Karathanasis, A.D., Call, D., Dinnes, D.L., Chatterjee, A. 2024. Fragipan horizon changes using annual ryegrass and other amendments. Open Journal of Soil Science. 14(6). https://doi.org/DOI:10.4236/ojss.2024.146021.
    
  • Interactive effects of humic product application with nitrogen fertilizer rates on corn grain yield in a central Iowa field study-(Abstract Only)
    Olk, D.C., Dinnes, D.L. 2023. Interactive effects of humic product application with nitrogen fertilizer rates on corn grain yield in a central Iowa field study [abstract]. ASA-CSSA-SSSA Annual Meeting. Paper No. 252-4.
    
  • Variable humic product effects on maize structural biochemistry across annual weather patterns and soil types in two Iowa (U.S.A.) production fields -(Peer Reviewed Journal)
    Olk, D.C., Dinnes, D.L., Hatfield, R.D., Scoresby, J.R., Darlington, J.W. 2023. Variable humic product effects on maize structural biochemistry across annual weather patterns and soil types in two Iowa (U.S.A.) production fields. Frontiers in Plant Science. 13. https://doi.org/10.3389/fpls.2022.1058141.
    
  • Stimulation of corn root growth by humic products in Iowa fields: implications for soil properties-(Abstract Only)
    Olk, D.C., Dinnes, D.L. 2022. Stimulation of corn root growth by humic products in Iowa fields: implications for soil properties [abstract]. ASA-CSSA-SSSA Annual Meeting. Paper No. 147-5.
    
  • Maize growth responses to a humic product in Iowa production fields: An extensive approach -(Peer Reviewed Journal)
    Olk, D.C., Dinnes, D.L., Callaway, C.R. 2022. Maize growth responses to a humic product in Iowa production fields: An extensive approach. Frontiers in Plant Science. 12. Article e778603. https://doi.org/10.3389/fpls.2021.778603.
    
  • Maize growth and grain yield responses to a micronized humic product across soil types and annual weather patterns in Central Iowa, United States -(Peer Reviewed Journal)
    Olk, D.C., Dinnes, D.L., Scoresby, R.J., Darlington, G.W., Hurburgh, C.R., Rippke, G.R. 2021. Maize growth and grain yield responses to a micronized humic product across soil types and annual weather patterns in Central Iowa, United States. Frontiers in Plant Science. 12. Article 672078. https://doi.org/10.3389/fpls.2021.672078.
    
  • Long-Term benefits of humic product application to soil organic matter and physical properties in Iowa corn-soybean rotations-(Abstract Only)
    Olk, D.C., Dinnes, D.L., Abdelrahman, H.M., Scoresby, R.J. 2019. Long-Term benefits of humic product application to soil organic matter and physical properties in Iowa corn-soybean rotations. In proceedings of ASA-SSSA-CSA Annual Meeting, Nov 10-13,2019, San Antonio, Texas. Available: https://scisoc.confex.com/scisoc/2019am/meetingapp.cgi/Paper/120820.
    
  • Application of a formulated humic product can increase soybean yield -(Peer Reviewed Journal)
    Lenssen, A.W., Olk, D.C., Dinnes, D.L. 2019. Application of a formulated humic product can increase soybean yield. Crop, Forage & Turfgrass Management. 5(1):1-6. https://doi.org/10.2134/cftm2018.07.0053.
    
  • Can humic products substantially improve ecosystem quality and economic yield?-(Peer Reviewed Journal)
    Olk, D.C., Dinnes, D.L., Scoresby, J.R., Callaway, C.R., Darlington, J.W. 2019. Can humic products substantially improve ecosystem quality and economic yield? Silva Balcanica. 20(1):95-110.
    
  • Humic products in agriculture: Potential benefits and research challenges-a review -(Peer Reviewed Journal)
    Olk, D.C., Dinnes, D.L., Scoresby, R., Callaway, C.R., Darlington, J.W. 2018. Humic products in agriculture: Potential benefits and research challenges-a review. Journal of Soils and Sediments. 18:2881-2891. https://doi.org/10.1007/s11368-018-1916-4.
    
  • Crop growth and production responses to commercial humic products in U.S. Midwestern rainfed conditions-(Abstract Only)
    
    
  • Field trials of Growmate humic products in Central and South America: benefits of networked sites.-(Abstract Only)
    
    
  • Occurrence and abundance of carbohydrates and amino compounds in sequentially extracted labile soil organic matter fractions.-(Peer Reviewed Journal)
    Abdelrahman, H., Olk, D.C., Dinnes, D.L., Ventrella, D., Cocozza, C. 2016. Occurrence and abundance of carbohydrates and amino compounds in sequentially extracted labile soil organic matter fractions. Journal of Soils and Sediments. 16(10):2375-2384. doi: 10.1007/s11368-016-1437-y.
    
  • Can humic products become mainstream amendments for improving crop production?-(Abstract Only)
    
    
  • On-farm evaluation of a humic product in Iowa (U.S.) maize production-(Book / Chapter)
    Olk, D.C., Dinnes, D.L., Callaway, C., Raske, M. 2013. On-farm evaluation of a humic product in Iowa (U.S.) maize production. In: Xu, J., Wu, J., He, Z., editors. Functions of Natural Organic Matter in a Changing Environment. Dordrecht, The Netherlands: Springer. p. 1047-1050.
    
  • Chemical properties of humic and fulvic acid products and their ores of origin-(Book / Chapter)
    Mao, J., Olk, D.C., Na, C., Dinnes, D.L., Chappell, M. 2013. Chemical properties of humic and fulvic acid products and their ores of origin. In: Xu, J., Wu, J., He, Z., editors. Functions of Natural Organic Matter in a Changing Environment. Dordrecht, The Netherlands: Springer. p. 1067-1070.
    
  • Field evaluation of a humic product in Iowa corn fields-(Abstract Only)
    
    
  • Midwest soil and water conservation: Past, present and future-(Book / Chapter)
    Karlen, D.L., Dinnes, D.L., Singer, J.W. 2010. Midwest soil and water conservation: Past, present and future. In: Zobeck, T.M., Schillinger, W.F., editors. Soil and Water Conservation Advances in the U.S.: Past Efforts and Future Outlook. Madison, WI: Soil Science Society of America, Inc. p. 131-162.
    
  • Is No-Tillage Enough? A Field-Scale Watershed Assessment of Conservation Effects-(Peer Reviewed Journal)
    Karlen, D.L., Dinnes, D.L., Tomer, M.D., Meek, D.W., Cambardella, C.A., Moorman, T.B. 2009. Is No-Tillage Enough? A Field-Scale Watershed Assessment of Conservation Effects. Journal of Integrative Biosciences. 7(2):1-24.
    
  • Three Analysis Examples for Time Series Data-(Abstract Only)
    Meek, D.W., Laird, D.A., Dinnes, D.L., Jaynes, D.B., Cambardella, C.A., Colvin, T.S., Hatfield, J.L., Karlen, D.L. 2008. Three Analysis Examples for Time Series Data [CD-ROM]. In: ASA-CSSA-SSSA Annual Meeting Abstracts, Oct. 5-9, 2008, Houston, TX.
    
  • Modeling Biochemical Impacts of Alternative Management Practices for a Row-Crop Field in Iowa-(Peer Reviewed Journal)
    Farahbakhshazad, N., Dinnes, D.L., Li, C., Jaynes, D.B., Salas, W. 2008. Modeling Biochemical Impacts of Alternative Management Practices for a Row-Crop Field in Iowa. Agriculture, Ecosystems and Environment. 123(1-3):30-48.
    
  • APPLICATION OF THE ANNAGNPS MODEL TO THE WALNUT CREEK, IA CEAP BENCHMARK WATERSHED-(Abstract Only)
    Dinnes, D.L., Jaynes, D.B., Karlen, D.L., Bingner, R.L., Yuan, Y. 2006. Application of the ANNAGNPS model to the Walnut Creek, IA CEAP benchmark watershed. 2006 USDA-ARS CEAP Watershed Assessment Study Annual Meeting. Available: www.nrcs.usda.gov/TECHNICAL/nri/ceap/watersheds/2006meeting.html.
    
  • TRANSLATING AGRICULTURAL WATER QUALITY RESEARCH RESULTS INTO A FORMAT FOR POLICYMAKERS TO USE-(Abstract Only)
    Dinnes, D.L., Jaynes, D.B., Hatfield, J.L. 2005. Translating agricultural water quality research results into a format for policymakers to use [CD-ROM]. In: ASA-CSSA-SSSA Annual Meeting Abstracts, Nov. 6-10, 2005, Salt Lake City, UT.
    
  • MODELING NITRATE LEACHING WITH A BIOGEOCHEMICAL MODEL MODIFIED BASED ON OBSERVATIONS IN A ROW-CROP FIELD IN IOWA-(Peer Reviewed Journal)
    Li, C., Farahbakhshazad, N., Jaynes, D.B., Dinnes, D.L., Salas, W., Mclaughlin, D. 2006. Modeling nitrate leaching with a biogeochemical model modified based on observations in a row-crop field in Iowa. Ecological Modeling. 196:116-130.
    
  • CORN RESPONSE TO LATE-SPRING NITROGEN MANAGEMENT IN THE WALNUT CREEK WATERSHED-(Peer Reviewed Journal)
    Karlen, D.L., Dinnes, D.L., Jaynes, D.B., Hurburgh, C.R., Cambardella, C.A., Colvin, T.S., Rippke, G.R. 2005. Corn response to late-spring nitrogen management in the Walnut Creek watershed. Agronomy Journal. 97:1054-1061.
    
  • ASSESSMENTS OF PRACTICES TO REDUCE NITROGEN AND PHOSPHORUS NONPOINT SOURCE POLLUTION OF IOWA'S SURFACE WATERS-(Other)
    Dinnes, D.L. Assessments of practices to reduce nitrogen and phosphorus nonpoint source pollution of Iowa's surface waters. Review Article. Available at: ftp://ftp.nstl.gov/pub/NPS/NPS Nutrient Pollution Assessments of Conservation Practices.pdf
    
  • THE EFFECTS OF N-FERTILIZER PRACTICES ON THE WATER QUALITY OF WALNUT CREEK, IOWA-(Abstract Only)
    Jaynes, D.B., Dinnes, D.L., Hatfield, J.L., Saleh, A., Arnold, J.G. 2004. The Effects of N-Fertilizer Practices on the Water Quality of Walnut Creek, Iowa [CD-ROM]. ASA-CSSA-SSSA Annual Meeting Abstracts. Madison, Wisconsin.
    
  • USING THE LATE SPRING NITRATE TEST TO REDUCE NITRATE LOSS WITHIN A WATERSHED-(Peer Reviewed Journal)
    JAYNES, D.B., DINNES, D.L., MEEK, D.W., KARLEN, D.L., CAMBARDELLA, C.A., COLVIN, T.S. USING THE LATE SPRING NITRATE TEST TO REDUCE NITRATE LOSS WITHIN A WATERSHED. JOURNAL OF ENVIRONMENTAL QUALITY. 2004. V. 33(2). P. 656-668.
    
  • CHARACTERIZATION OF WATER AND NITRATE FLUXES FROM A TILE-DRAINED WATERSHED-(Abstract Only)
    TOMER, M.D., JAYNES, D.B., HATFIELD, J.L., COLE, K.J., DINNES, D.L., JAQUIS, R.J. CHARACTERIZATION OF WATER AND NITRATE FLUXES FROM A TILE-DRAINED WATERSHED. SOIL AND WATER CONSERVATION SOCIETY. 2002. V. 57(5). P. 325.
    
  • SURFACE WATER QUALITY RESPONSE TO A NITROGEN FERTILIZER BMP AT THE WATERSHED SCALE-(Abstract Only)
    DINNES, D.L., JAYNES, D.B., KARLEN, D.L., MEEK, D.W., CAMBARDELLA, C.A., COLVIN, T.S., HATFIELD, J.L. SURFACE WATER QUALITY RESPONSE TO A NITROGEN FERTILIZER BMP AT THE WATERSHED SCALE. SOIL AND WATER CONSERVATION SOCIETY. 2002. V. 57(5). P. 308.
    
  • A SITE-SPECIFIC EVALUATION OF A CROP-DENITRIFICATION/DECOMPOSITION MODEL BASED UPON A US MIDWESTERN ROW-CROP FIELD-(Proceedings)
    FARAHBAKHSHAZAD, N., MCLAUGHLIN, D., DINNES, D.L., JAYNES, D.B., LI, C. A SITE-SPECIFIC EVALUATION OF A CROP-DENITRIFICATION/DECOMPOSITION MODEL BASED UPON A US MIDWESTERN ROW-CROP FIELD. INTERNATIONAL CONFERENCE ON PRECISION AGRICULTURE ABSTRACTS & PROCEEDINGS. 2002. CD-ROM. Madison, WI: ASA-CSSA-SSSA.
    
  • FLOW-DURATION CHARACTERIZATION OF WATER AND NITRATE FLUXES FROM A TILE-DRAINED WATERSHED-(Abstract Only)
    TOMER, M.D., BURKART, M.R., JAYNES, D.B., JAQUIS, R.J., COLE, K.J., HATFIELD, J.L., DINNES, D.L. FLOW-DURATION CHARACTERIZATION OF WATER AND NITRATE FLUXES FROM A TILE-DRAINED WATERSHED. AMERICAN SOCIETY OF AGRONOMY MEETINGS. 2001. CD-ROM. MADISON, WI.
    
  • NITROGEN MANAGEMENT STRATEGIES TO REDUCE NITRATE LEACHING IN TILE-DRAINED MIDWESTERN SOILS-(Review Article)
    DINNES, D.L., KARLEN, D.L., JAYNES, D.B., KASPAR, T.C., HATFIELD, J.L., COLVIN, T.S., CAMBARDELLA, C.A. NITROGEN MANAGEMENT STRATEGIES TO REDUCE NITRATE LEACHING IN TILE-DRAINED MIDWESTERN SOILS. AGRONOMY JOURNAL. 2002. V. 94. P. 153-171.
    
  • PLANT-SOIL-MICROBE N RELATIONSHIPS IN HIGH RESIDUE MANAGEMENT SYSTEMS-(Proceedings)
    DINNES, D.L., JAYNES, D.B., KASPAR, T.C., COLVIN, T.S., CAMBARDELLA, C.A., KARLEN, D.L. PLANT-SOIL-MICROBE N RELATIONSHIPS IN HIGH RESIDUE MANAGEMENT SYSTEMS. SOUTH DAKOTA NO TILL ASSOCIATION ANNUAL CONFERENCE. 2001. P. 45-50.
    
  • N MANAGEMENT AND HYPOXIA: A RESEARCH FOCUS OF THE USDA-ARS NATIONAL SOIL TILTH LABORATORY-(Abstract Only)
    Dinnes, D.L., Jaynes, D.B., Hatfield, J.L., Burkart, M.R., Parkin, T.B., Cambardella, C.A., Karlen, D.L., Colvin, T.S., Kaspar, T.C., James, D.E. 2001. N management and hypoxia: A research focus of the USDA-ARS National Soil Tilth Laboratory. Farm Bureau Members National Convention. American Farm Bureau Federation, Washington, D.C.
    
  • A FUNCTIONAL TREE, SHRUB AND GRASS BUFFER FOR A CONFINED ANIMAL FEEDING FACILITY-(Abstract Only)
    Hunt, R., Christensen, D., Colletti, J., Dinnes, D.L., Hatfield, J.L. 2000. A functional tree, shrub and grass buffer for a confined animal feeding facility. Innovative technologies for planning animal feeding operations, comprehensive nutrient management planning program and proceedings. p. 192-200.
    
  • REDUCING N CONTAMINATION OF SURFACE WATERS FROM TILE-DRAINED SOILS AT THE WATERSHED SCALE-(Abstract Only)
    Dinnes, D.L., Jaynes, D.B., Meek, D.W., Cambardella, C.A., Colvin, T.S., Hatfield, J.L., Karlen, D.L. 2000. Reducing n contamination of surface waters from tile-drained soils at the watershed scale [CD-ROM]. ASA-CSSA-SSSA Annual Meeting Abstracts. Madison, Wisconsin.
    
  • WATERSHED SCALE INTENSIVE NITROGEN FERTILIZER MANAGEMENT REDUCES NITROGEN CONTAMINATION OF SURFACE WATERS-(Abstract Only)
    
    
  • AN AUTOREGRESSION MODEL FOR A PAIRED WATERSHED COMPARISON-(Proceedings)
    MEEK, D.W., DINNES, D.L., JAYNES, D.B., CAMBARDELLA, C.A., COLVIN, T.S., HATFIELD, J.L., KARLEN, D.L. AN AUTOREGRESSION MODEL FOR A PAIRED WATERSHED COMPARISON. APPLIED STATISTICS IN AGRICULTURE CONFERENCE PROCEEDINGS. 2000. P. 223-231.
    
  • AN AUTOREGRESSION MODEL FOR A PAIRED WATERSHED COMPARISON-(Proceedings)
    Meek, D.W., Dinnes, D.L., Jaynes, D.B., Cambardella, C.A., Colvin, T.S., Hatfield, J.L., Karlen, D.L. 2000. An autoregression model for a paired watershed comparison. Proceedings of the 12th Applied Statistics In Agriculture Conference. p. 223-231.
    
  • INTENSIVE N FERTILIZER MANAGEMENT EFFECTS ON WATER QUALITY AT THE WATERSHED SCALE-(Abstract Only)
    Dinnes, D.L., Jaynes, D.B., Cambardella, C.A., Colvin, T.S., Hatfield, J.L., Karlen, D.L. 2000. Intensive N fertilizer management effects on water quality at the watershed scale. Proceedings of the Watershed Approach to Improving Water Quality: Fact or Fantasy? Soil and Water Conservation Society. p. 95-99.
    
  • INTENSIVE N FERTILIZER MANAGEMENT EFFECTS ON WATER QUALITY AT THE WATERSHED SCALE-(Proceedings)
    
    
  • INTENSIVE NITROGEN FERTILIZER MANAGEMENT EFFECTS ON WATER QUALITY AT THE WATERSHED SCALE-(Abstract Only)
    Dinnes, D.L., Jaynes, D.B., Meek, D.W., Cambardella, C.A., Colvin, T.S., Hatfield, J.L., Karlen, D.L. 2000. Intensive nitrogen fertilizer management effects on water quality at the watershed scale. Proceedings of Agriculture and the Environment: A Wake-Up Call for Iowans. Iowa State University Extension, Ames, Iowa.
    
  • INTENSIVE N FERTILIZER MANAGEMENT EFFECTS ON WATER QUALITY AT THE WATERSHED SCALE-(Abstract Only)
    Dinnes, D.L., Jaynes, D.B., Cambardella, C.A., Colvin, T.S., Hatfield, J.L., Karlen, D.L. 1999. Intensive n fertilizer management effects on water quality at the watershed scale [CD-ROM]. ASA-CSSA-SSSA Annual Meeting Abstracts. Madison, Wisconsin.
    
  • SPLIT APPLICATION NITROGEN FERTILIZER MANAGEMENT EFFECTS ON CORN YIELD AND WATER QUALITY-(Popular Publication)
    Dinnes, D.L., Jaynes, D.B., Cambardella, C.A., Colvin, T.S., Hatfield, J.L., Karlen, D.L. 1999. Split application nitrogen fertilizer management effects on corn yield and water quality. Farm Bureau Spokesman Press. 1999 Autumn Harvest Issue. Iowa Farm Bureau, West Des Moines, Iowa.
    
  • NITRATE-NITROGEN LOADS IN SUBSURFACE DRAINED SOILS IN CENTRAL IOWA-(Abstract Only)
    
    
  • EFFECTS OF AN OPTIMUM FERTILIZER PROGRAM ON CORN YIELD AND WATERSHED WATER QUALITY-(Abstract Only)
    
    
  • EFFECTS OF AN OPTIMUM N FERTILIZER PROGRAM ON CORN YIELD AND WATERSHED WATER QUALITY-(Abstract Only)
    
    
  • POTENTIAL FOR NITROGEN FERTILIZER VARIABLE RATE MANAGEMENT: A CASE STUDY-(Experiment Station)
    
    
  • REDUCING AGRICULTURE'S CONTRIBUTION TO NITRATE CONTAMINATION OF SURFACE WATERS-(Proceedings)
    
    

• Projects

  No projects listed for this employee.

• ARS News Articles

  No news articles listed for this employee.