Andrew Lenssen
Research Weed Ecologist
Phone: 406.433.9471
Fax: 406.433.5038
E-mail: alenssen@sidney.ars.usda.gov
Additional Pages: Research Projects,* Publications*
*Taken from the Agricultural Research Information System (ARIS) database.
EDUCATION
B.S. Agronomy | 1980 | Cornell University, Ithaca, New York |
M.S. Agronomy | 1987 | Kansas State University, Manhattan, Kansas |
Ph. D. Agronomy | 1989 | Kansas State University, Manhattan, Kansas |
CURRENT RESEARCH
Andy’s research program directly addresses three areas, 1) developing diverse irrigated and dryland cropping strategies and technologies for improved weed management, 2) quantify environmental benefits from improved weed management, particularly for management of herbicide resistant weeds, and 3) extend research results and increase adoption rates of sustainable weed management and crop production practices in irrigated and dryland environments. Specifically, his field studies involve determining the influence of diversifying and intensifying the durum-fallow dryland system with annual forage, pulse and/or oilseed crops on weed species diversity, weed biomass, soil seed bank, water and nitrogen use, and crop yield and quality. Other field studies examine cultural methods, such as seeding rate, row spacing, fertilization practices, or rolling to reduce herbicide use without compromising weed control, crop yield or quality. Irrigated field studies include determining weed seed numbers in irrigation waters, and the influence of crop rotation and previous crop on kochia and other weeds in sugar beet production. Laboratory investigations include determining the influence of phytochemistry on weed seed destruction by arthropods and soil microbes.
RESEARCH EXPERIENCE
Over the past 10 years, Andy has led collaborative, multidisciplinary team projects investigating intensified, diversified dryland crop rotations and their influences on wheat and alternate crop productivity and quality, weeds, insects and diseases, and potential environmental and economic benefits. He has utilized global positioning systems with geographic information systems on field-scale research plots to compare soil water and nitrate, crop yield and quality, and weeds, insects, and diseases, in conventional and diversified dryland wheat rotations in Montana. He has been Project Director and Principal Investigator of the Sustainable Pest Management in Dryland Wheat project, with research sites near Froid (21 acres), Havre (50 acres), and Moore (35 acres), Montana. Results from these projects have documented that some diversified crop rotations, particularly those utilizing zero tillage, can improve grain yield and quality, decrease plant diseases such as Fusarium Crown Rot, decrease herbicide use and weed interference, and use fertilizer nitrogen and precipitation more efficiently than conventional wheat-fallow systems. He has extensive experience developing and integrating cultural controls of pests into production systems, including alfalfa. He also has extensive research experience in irrigated grain and irrigated and dryland forage management and utilization. Technology transfer has been through scientific press, web documents, national and regional professional meetings, and numerous field visits and Cooperative Extension meetings. He has made numerous invited presentations to university departments, Extension meetings, action agencies, and grower groups.
RELATED WEBPAGES
Sustainable pest management in dryland wheat project
Pacific Northwest Canola Funded Research
SELECTED PUBLICATIONS
Sainju, U.M., Lenssen, A.W., Caesar, T., Waddell, J.T. 2006. Tillage and Crop Rotation Effects on Dryland Soil and Residue Carbon and Nitrogen. Soil Science Society of America Journal. 70:668-678.
Sainju, U.M., Lenssen, A.W., Caesar, T., Waddell, J.T. 2006. Tillage and Crop Rotation Effects on Dryland Soil and Residue Carbon and Nitrogen. Soil Science Society of America Journal. 70:668-678.
Hatfield, P., Blodgett, S., Spezzano, T., Goosey, H., Lenssen, A., and Kott, R. 2005. Incorporating Sheep into Dryland Grain Production Systems: i Impact on Over-wintering Larva Populations of Wheat Stem Sawfly, Cephus Cinctus Norton, (Hymenoptera: Cephidae). Small Ruminant Research.
Hatfield, P., Lenssen, A., Spezzano, T., Blodgett, S., Goosey, H., and Kott, R. 2005. Incorporating Sheep Into Dryland Grain Production Systems: ii Impact on Changes in Biomass and Weed Density. Small Ruminant Research.
Hatfield, P., Goosey, H., Spezzano, T., Blodgett, S., Lenssen, A., and Kott, R. 2005. Incorporating Sheep Into Dryland Grain Production Systems: iii Impact on Changes in Soil Bulk Density and Soil Nutrient Profiles. Small Ruminant Research.
Sainju, U.M., Lenssen, A.W., Caesar, T., Waddell, J.T. 2005. Carbon Sequestration in Dryland Soil and Plant Residue As Affected by Tillage and Crop Rotation. Third USDA Symposium on Greenhouse Gas Emissions and Carbon Sequestration in Agriculture and Forestry. P. 211.
Goosey, H.B., Hatfield, P.G., Lenssen, A.W., Blodgett, S.L., Kott, R.W., Spezzano, T.M. 2005. the Potential Role of Sheep in Dryland Grain Production Systems. Agriculture, Ecosystems and Environment. 111:349-353.
Blodgett, S.L., Lenssen, A.W. 2004. Distribution of Alfalfa Weevil (Coleoptera: Curculionidae) Larvae among Post-Cutting Locations. Journal of Economic Entomology. 97(4):1319-1322.
Peterson, R.K.D., C.L. Shannon, and A.W. Lenssen. 2004. Photosynthetic Responses of Legume Species to Actual and Simulated Insect Defoliation. Environmental Entomol. 33:450-456.
Lenssen, A.W., J.D. Banfield, and S.D. Cash. 2001. Trichome density influences drying rate of alfalfa forage. Grass and Forage Sci. 56:1-9.
Blodgett, S.L., A.W. Lenssen and S.D. Cash. 2000. Swathing with early raking for control of alfalfa weevil (Coleoptera: Curculionidae). J. Entomol. Sci. 35:129-135.
Cash, S.D., Zamora, D.L. and A.W. Lenssen. 1998. Viability of weed seeds in feed pellet processing. J. Range Manage. 51:181-185.
Lenssen, A.W., S.S. Martin, and C.E. Townsend. 1995. Clonal-by-environment interactions influence isoflavonoid accumulation in Astragalus cicer. Crop Sci. 35:756-753.
Martin, S.S., C.E. Townsend, and A.W. Lenssen. 1994. Induced isoflavonoids in diverse populations of Astragalus cicer. Biochem. Syst. Ecol. 22:657-661.
Posler, G.L., A.W. Lenssen, and G.L. Fine. 1993. Forage yield, quality, persistence, and compatibility of grass-legume mixtures. Agron. J. 85:554-560.
Lenssen, A.W., E.L. Sorensen, G.L. Posler, and D.L. Stuteville. 1991. Resistance to anthracnose protects forage quality of alfalfa. Crop Sci. 31:147-150.
Lenssen, A.W., E.L Sorensen, G.L. Posler, and L.H. Harbers. 1991. Basic alfalfa germplasms differ in nutritive value of forage. Crop Sci. 31:293-296.
Lenssen, A.W., E.L. Sorensen, and G.L. Posler. 1990. Forage quality of genetically diverse alfalfa germplasms at four phenological growth stages. Euphytica 51:53-57.
Lenssen, A.W., E.L. Sorensen, G.L. Posler, and L.H. Harbers. 1989. Sheep preference of perennial erect glandular-haired and eglandular Medicago populations under free-choice conditions. Crop Sci. 29:65-68.
Lenssen, A.W., E.L Sorensen, G.L. Posler, and L.H. Harbers. 1988. Forage quality of perennial glandular-haired and eglandular Medicago populations. Crop Sci. 28:168-171.
SELECTED PROCEEDINGS & ABSTRACTS
Blodgett, S., Lenssen, A., and Cash, S. 2005. Black Grass Bug Damages Intermediate Wheatgrass Quality. Research Notes, The Canadian Entomologist.
Sainju, U., Lenssen, A., Evans, R., Caesar, T., and Waddell, J. 2005. Tillage, Crop Rotations, and Cultural Practices Effects on Dryland Soil and Crop Residue Carbon and Nitrogen. Abstract, International Conference on Sustainable Agriculture for Food, Energy and Industry.
Lenssen, A.W. 2005. Preplant Weed Management and Planting Date Influence Barley Forage Yield and Quality. Asa-Cssa-Sssa Annual Meeting.
Lenssen, A.W., Johnson, G.D. 2005. Yield, Quality, Water Use, and Weeds in Annual Forage-Spring Durum Cropping Systems. Asa-Cssa-Sssa Annual Meeting Abstracts. Agronomy Abstracts. Abstract Number 6047. Cd-Rom.
Baril, R.A., Lenssen, A.W., Blodgett, S., Taper, M.L. 2004. Species Distribution, Regional Assemblages and Parasitism of Lygus in Montana Canola Fields. In: Proceedings of the Entomological Society of America Regional Meetings. Pacific Branch Annual Meeting of the Entomological Society of America, June 23, 2004, Bozeman, Mt.
Spezzano, T.M., H.B. Goosey, P.G. Hatfield, S.L. Blodgett, S.D. Cash, P.M. Denke, R.W. Kott, A.W. Lenssen, C.B. Marlow. 2003. Managing insect pest damage to wheat and alfalfa by integrating sheep into crop production. pp. 1-6, Proceedings of the Montana Nutrition Conference, Bozeman, MT.
Long, D.S., C. Meier, R.E. Engel, and A. Lenssen. 2002. Landscape elements as a basis for nitrogen management zones in Montana. p. 46 52. Proceedings of the Great Plains Soil Fertility Conference, 5-6 Mar. 2002, Denver, CO.
Lenssen, A.W., S.L. Blodgett, S.D. Cash, and P.M. Denke. 1998. Early raking reduces alfalfa weevil populations. in: Proceedings of the Montana Hay Growers Association, Billings, MT. p. 38-41.