Mark VanGessel
Areas of Responsibility
bluedot.gif (1301 bytes) Extension
extension program focuses on developing and disseminating weed control recommendations and other technical information appropriate to agronomic and commercial vegetable crops.  Technical information emphasizes weed biology and ecology.  Extension responsibilities include weed management for agronomic crops in New Jersey.
bluedot.gif (1301 bytes) Research
Research efforts fall into five main areas: weed biology and ecology, integrated pest management, perennial weed management, herbicide-resistant weeds, and herbicide evaluation.  Research has focused on agronomic and commercial vegetable crops important to the mid-Atlantic region.

Contact Information

University of Delaware
Research and Education Center
16483 County Seat Highway

Georgetown, DE 19947

302/856-7303 ext 510
302/856-1845 (fax)



 Extension Specialist  &
Professor for Weed/Crop Management


Ph.D., Weed Science, Crop Science Department, North Carolina State University.  1992. 

M.Sc., Weed Science, Crop and Soil Sciences Department, Michigan State University.

B.A., Political Science, Hope College, Holland, MI.

Professional Experience

2005 to present.  Professor/Extension Specialist.  Department of Plant and Soil Science, University of Delaware.

1999 to 2005.
  Associate Professor/Extension Specialist.  Department of Plant and Soil Science, University of Delaware.

1995 to 1999.
  Assistant Professor/Extension Specialist.  Department of Plant and Soil Science, University of Delaware.

1992 to 1995.
  Research Post-Doctoral Associate.  Plant Pathology and Weed Science Department, Colorado State University.

1983 to 1985.
  U.S. Peace Corps Volunteer, Fish Production, Lesotho, southern Africa.

Professional Activities

  Weed Science Society of America
  International Weed Science Society
  Northeastern Weed Science Society
  Agronomy Society of America
  Council of Agricultural Science and Technology
  Delaware Invasive Species Council

Publications (Selected Listing)

   Extension Publications (available at

Pasture and Hay Weed Management Guide

Soybean weed management guide: for Delaware and New Jersey

Corn weed management guide: for Delaware and New Jersey

Sweet corn hybrid tolerance to Callisto and Accent

Large plot test-demonstrations for evaluating weed control

Determining presence of glyphosate-resistant horseweed under field conditions.

   Research Publications

Book Chapters

Christoffoleti, P., S.J. Pinto de Carvalho, M. Nicola, D. Doohan, and M. VanGessel.  2007.  Prevention strategies in weed management.  In Non-chemical weed management: principles, concepts, and technology, Editors: Mahesh Upadhyaya and Robert Blackshaw.  CABI, Oxfordshire, UK.

      Selected Journal Articles

Zelaya, I.A., M.D.K. Owen, and M.J. VanGessel.  2007.  Transfer of glyphosate resistance:  evidence for hybridization in Conyza (Asteraceae).  American Journal of Botany 94:660-673.

Dauer, J.T., D.A. Mortensen, and M.J. VanGessel.  2007.  Temporal and spatial dynamics of long-distance Conyza canadensis seed dispersal.  Journal of Applied Ecology 44:105-114.

Myers, M.W, W.S. Curran, M.J. VanGessel, B.A. Majek, D.D. Calvin, D.A. Mortensen, H.D. Karsten, and G.W. Roth.  2005.  Effect of spring disturbance on annual weed emergence in the northeastern United States.  Weed Technology 19:274-282.

elaya, I.A., M.D.K. Owen, and M.J. VanGessel.  2004.  Inheritance of evolved glyphosate resistance in Conyza canadensis (L.) Cronq.  Theoretical Applied Genetics 110:58-70.

Hough-Goldstein, J.A., M.J. VanGessel, and A.P. Wilson.  2004.  Manipulation of weed communities to enhance ground-dwelling arthropod populations in herbicide-resistant field corn.  Environmental Entomology 33:577-586.

Whaley, C. and M.J. VanGessel.
  2002.  Horsenettle (Solanum carolinense) control with a field corn (Zea mays) weed management program.  Weed Technology 16:293-300.

VanGessel, M.J.
  2001.  Glyphosate-resistant horseweed from Delaware.  Weed Science 49:703-705.

VanGessel, M.J., A.O. Ayeni, and B. Majek.
  2001.  Glyphosate in full-season no-till glyphosate-resistant soybean: role of preplant applications and residual herbicides.  Weed Technology 15:714-724.

Sankula, S., M.J. VanGessel, W.E. Kee, and J. Glancey.  1999.  Impact of row spacing, herbicide rate and application method on weed control and harvest efficiency of lima bean.  HortTechnology, 9:633-637.

VanGessel, M.J.,
  E.E. Schweizer, R.G. Wilson, L.J. Wiles, and P. Westra.  1998.  Impact of timing and frequency of in-row cultivation for weed control in dry bean (Phaseolus vulgaris).  Weed Technology 12:548-553.

VanGessel, M.J., J. Schroeder, and P. Westra.
  1997.  Comparative growth and development of four spurred anoda (Anoda cristata) accessions.  Weed Science 46:91-98.

VanGessel, M.J. and H.D. Coble.
  1993.  Postemergence control of johnsongrass and its effect on maize dwarf mosaic virus incidence and vectors in corn.  Plant Disease 77:613-618.

VanGessel, M.J. and K.A. Renner.  1990.  Redroot pigweed (Amaranthus retroflexus) and barnyardgrass (Echinochloa crus-galli) interference in potatoes (Solanum tuberosum).  Weed Science 38:338-343.

All Refereed Publications [+]