"Extension programs for small vegetable farms." American Society for Horticultural Science Annual Meeting. Ames, IA. August 9-13, 1982.
"Applications of plant growth substances as seed additives for improved germination and vigor of crops." Annual Meeting of the Plant Growth Regulator Society of America. East Lansing, MI. June 21, 1983.
"Current issues in extension." American Society for Horticultural Science Annual Meeting. McAllen, TX. October 16-21, 1983.
"New sweet corn hybrids - genetics, production and post harvest physiology." Michigan State University, East Lansing, MI. January 24, 1984.
Three presentations on vegetable production and physiology at the Great Lakes Vegetable Growers Meeting in Lansing, MI. January 25, 1984.
"Production and marketing of vegetables." Indiana Fruit and Vegetable Growers Conference. Indianapolis, IN. February 2, 1984.
Two presentations on sweet corn genetics and production at the Kansas Sweet Corn Workshop. Wichita, KS. February 15, 1984.
Three presentations on production topics to vegetable growers at the Iowa Fruit and Vegetable Conference. Des Moines, IA. February 6-7, 1985.
"Nutrient solution management for optimum plant growth." Hydroponics Worldwide: State of the Art in Soilless Crop production. Honolulu, Hawaii. February 18-22, 1985.
Three presentations on production topics to greenhouse growers on at the Texas Greenhouse Growers Conference, Tyler, TX. July 19-22, 1985.
"Hydroponic Vegetable Growing." Iowa Greenhouse Growers Workshop. Davenport, IA. October 24, 1985.
"Commercial production of greenhouse tomatoes and lettuce." North Carolina Vegetable Greenhouse Conference. Raleigh, NC. November 21, 1985.
Three presentations on production topics to vegetable growers at the Great Lakes Vegetable Growers Meeting. Lansing, MI. January 29, 1986.
Two presentations on production topics to vegetable growers at the Indiana Vegetable Convention. Indianapolis, IN. February 12, 1986.
"Hydroponic Lettuce Growing." Indiana Greenhouse Vegetable Growers Convention. Indianapolis, IN. February 12, 1986.
Two presentations on production topics to the Texas Greenhouse Growers Convention, San Antonio, TX. July 20-21, 1986.
Panel discussion on hydroponic lettuce production at the American Greenhouse Vegetable Growers Association Annual Meeting. Cleveland, OH. Sept. 29 - October 1, 1986.
"New seeding technologies for vegetables." Illinois Fruit and Vegetable Growers Convention and Trade Show. Springfield, IL. January 15, 1987.
"Sweet corn physiology and culture." National Sweet Corn Evaluation Days, Osbost, Victoria, Australia. February 25, 1987.
"The use of row tunnels for early production of fresh market vegetables." New Town Agricultural Research Laboratory, Hobart, Tasmania, Australia. March 6, 1987.
"New seeding technologies for vegetable crops." Stoney Rise Vegetable Research Laboratory, Devonport, Tasmania, Australia. March 13, 1987.
"U.S. melon production: production and marketing." Dept. of Agriculture and Rural Affairs Mildura, Victoria, Australia. April 2, 1987.
"The future of extension programming in horticulture: a U.S. perspective." Department of Agriculture, Adelaide, South Australia. April 15, 1987.
"Sweet corn culture, physiology, and genetics." Frankston Vegetable Research Station, Frankston, Victoria, Australia. April 28, 1987.
"Research and educational programs on commercial vegetable crops." Dept. of Agriculture and Rural Affairs, Knoxfield Horticulture Research Institute, Victoria, Australia. May 15, 1987.
"Vegetable production in the U.S." Dept. of Agriculture and Rural Affairs, Ballarat, Victoria, Australia. May 18, 1987.
"Responding to the challenges of extension." Keynote address at the Annual Victorian Extension Conference. Dookie, Australia, June 23-26, 1987.
"Processing tomato production and contracts in the Midwestern U.S." Annual Australian Tomato Industry Symposium on Policy. Moana, NSW, Australia. July 30, 1987.
"Hydroponic greenhouse vegetable production in the U.S." Hydroponics Society of Victoria, Melbourne, Australia. August 12, 1987.
"The future of extension programming in horticulture: a U.S. perspective." Queensland Dept. of Primary Industries, Bundaberg, Queensland, Australia. October 13, 1987.
"Research results on row tunnels for melons and growing high sugar sweet corn." Horticulture Research Centre, Bundaberg, Queensland, Australia. October 15, 1987.
Two presentations on production topics to vegetable growers at the Kansas Fruit and Vegetable Growers Convention and Trade Show. Manhattan, KS. November 30 - December 1, 1988.
"Sweet corn production and marketing opportunities in Australia." National Sweet Corn Breeders Association Annual Meeting. Singer Island, Florida. January 16-21, 1989.
"Agroecological approaches to the quest for sustainability." Michigan State University, East Lansing, MI. November 21, 1989.
"Agroecology, innovation, and the Cooperative Extension Service." Keynote Address. UI Extension Annual Conference. Champaign, IL. November 29, 1989.
"The University of Illinois' New Agro-Ecology Program." National Conference on Sustainable Agriculture. Lincoln, NE. August 15-18, 1990.
"Agricultural sustainability: a global perspective." USAID Workshop on Agricultural Sustainability. Lusaka, Zambia, September 18-22, 1990.
"Change, leadership and vision: some thoughts on the future of extension programming." Extension Futures Workshop. West Palm Beach, FL. September 27-28, 1990.
"The sustainability ethic: questions raised by the impact of agricultural production on society." National Association for Continuing Education. Cedar Rapids, IA. October 8-9, 1990.
"Agroecological approaches to sustainability." Illinois Soil and Water Conservation Society. Champaign, IL. November 8-9, 1990.
"A state universities experience at sustainable agriculture program development." Sustainable Agriculture Conference. Gainesville, FL. December 4-5, 1990.
"Sustainable Agriculture and the Land-Grant System: Discovering the Common Ground." Sustainable Agriculture Quarterly Seminar, Ohio State University, Columbus, OH. May 21, 1991.
"Agro-Ecology: A Scientific Framework for Sustainable Agriculture." Cornell University, Ithaca, NY. September 19, 1991.
"Farmer Participation in Research; A Model for Adaptive Research and Education." Conference on Innovative Policies for Agricultural Research. Tufts Univ., Boston, MA. November, 21-22,1991.
"The Benefits of Adaptive On Farm Research to the Agricultural Community and University." Keynote address in the conference, Profitable Agriculture and a Clean Environment, University of Maryland. Annapolis, Maryland, January 23, 1992.
"Necessary Changes in the Land Grant System." Vermont Sustainable Agriculture Conference, December 10, 1993. Stowe, VT.
"Environmentalists Can be Your Best Customers." New England Small Fruit and Vegetable Conference. December 15, 1993. Sturbridge, MA.
"Integrating Research and Extension Education in Agricultural Sciences." 65th Annual Meeting of the Eastern Branch of the Entomological Society of America. February 28, 1994. Newport, RI.
"New Models for Research and Extension Education." Northeast Division of the American Society of Agronomy Annual Meeting. July 11, 1994. Montreal, Canada.
"The New England Extension Consortium: Integrating Research and Extension Across a Region." Annual Meeting of the American Society for Horticultural Science. August 8, 1994. Corvallis, Oregon.
"The Death of the Land Grant System and Opportunities for Rebirth." Northeast Sustainable Agriculture Working Group. Coventry, Rhode Island. November 11, 1994.