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  • School of Integrative Plant Science
  • Soil and Crop Sciences Section
  • Agriculture
  • Organic
  • Crops

Cornell and USDA scientists have produced the definitive guide to understanding agricultural weeds and how to manage them efficiently, effectively and ecologically. The 416-page book, Manage Weeds on Your Farm: A Guide to Ecological Strategies,” was published by the USDA’s Sustainable Agriculture Research and Education (SARE) Program.

“It’s an amazing resource, exactly the kind of publication growers are looking for,” said Chris Smart, director of the School of Integrative Plant Science (SIPS) in Cornell’s College of Agriculture and Life Sciences. “It is both thorough and user-friendly. And who isn’t looking for better strategies to control weeds on their farm?”

The lead author, Charles “Chuck” Mohler, Ph.D. ’79, was a senior research associate in SIPS’ Soil and Crop Sciences Section, who died unexpectedly April 1, 2021. He worked closely with co-author Antonio DiTommaso, the section’s chair and head of Cornell’s Weed Ecology and Management Lab. Retired USDA-ARS weed scientist John Teasdale helped complete the volume.

“Chuck was a brilliant scientist and a key weed science innovator who brought ecological knowledge, scientific rigor and elegant experimental design to weed studies,” said DiTommaso. “But his true talent was his ability to translate this often highly technical research into practical and useful information and advice for growers.”

Based on that strong research foundation, the guide identifies the best tactics and timing for how to outsmart 63 particularly pernicious weed species, while reducing labor and ensuring weed competition doesn’t reduce yields. As new scientific findings on these species become available, DiTommaso will provide updates on his website.

“This book has the best information on weed management that is available today,” said pioneering organic farmer Klaas Martens of Lakeview Organic Grain in Penn Yan, New York. “Our understanding of weed control is still growing rapidly, and this book will certainly become an invaluable tool for every farmer who wants to control their weeds sustainably.”

Manage Weeds on Your Farm is available as a free download from the SARE website. The print version will be available in February 2022.

Meet the authors

Chuck Mohler

In addition to his passion to push the field of weed science from a focus on chemical weed control in new directions, Mohler was known for his inspirational leadership – generously sharing his time and expertise with growers, students and other scholars.

Mohler co-authored four other influential books, including “Ecological Management of Agricultural Weeds (2001) and “Crop Rotation on Organic Farms: A Planning Manual (2009). He also devoted his life to organic farming and sustainability, and he lived simply. He built his own home, split his own wood, and grew and canned his own vegetables.

Meet the authors

Toni DiTommaso

A professor and chair of the Soil and Crop Sciences Section of the School of Integrative Plant Science, DiTommaso also helped grow the ag sciences major as the first Richard C. Call Director of Agricultural Sciences, from 2011 to 2021. He joined the Cornell faculty in 1999 after serving as a lecturer at McGill University.

DiTommaso teaches popular hands-on courses in weed science and integrated pest management, maintains an active research program, and has served as president of the Northeastern Weed Science Society and has been editor of the journal Invasive Plant Science and Management since 2015. Many graduate and undergraduate students know him best as the enthusiastic faculty adviser of the Cornell Weed Science Team, which travels each summer to regional and national collegiate weed competitions. Pictured: DiTommaso (front row, center) with the 2017 team.

Meet the authors

John Teasdale

Teasdale is a recently retired USDA Agricultural Research Service weed scientist who served as the lead scientist of the Sustainable Agricultural Systems Lab Weed Ecology Project and contributed to the Farming Systems Project at the USDA’s Beltsville Agricultural Research Center in Maryland. 

His research has focused on integrating cover crops into cropping systems to help suppress weeds and provide other ecological services.

“With Chuck’s failing eyesight and untimely death, it was enormously helpful to have John come on as a co-author during the last two years of this project,” said DiTommaso.

mohler explaining cultivation equipment to farmers at field day
ditommaso with students on the weed science team
teasdale in field with hairy vetch cover crop

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