Ecologically based weed management: A manual and training program for farm advisors

2007 Annual Report for ENE06-099

Project Type: Professional Development Program
Funds awarded in 2006: $129,670.00
Projected End Date: 12/31/2009
Region: Northeast
State: New York
Project Leader:
Dr. Charles Mohler
Cornell University

Ecologically based weed management: A manual and training program for farm advisors


Farm surveys and case studies show that weeds often cause substantial problems for organic farmers and others who avoid the use of herbicides. Nevertheless, weeds are consistently well controlled on some organic farms. Many cultural and mechanical procedures are available for suppressing weeds in sustainable cropping systems. A key factor in successful weed management in sustainable agriculture, however, appears to be sound understanding of the biology of weeds and how to use weed biology to leverage effective management.

We propose to develop a manual on ecologically based weed management and use this in a series of training workshops for extension personnel throughout the Northeast. The manual will include sections covering the biology of various types of weeds, explain the advantages and limitations of various cultural procedures, and discuss how to effectively apply various types of tillage and cultivation. The manual will also discuss identification, ecological characteristics, and management of 75 major weeds, 80% of which are problems for growers in the Northeast. Finally, it will discuss how ecological weed management is integrated on real farms.

An Advisory/Training Team of ten farm educators will review and critique the manual. They will also assist in a series of eight workshops for extension personnel held throughout the Northeast. Workshops will explain principles of weed biology and ecologically based weed management, and then train participants on use of the manual for solving weed problems.

The project will be evaluated through extension activity logs of the Advisory/Training Team, and surveys of workshop attendees.

Objectives/Performance Targets

Target 1. Of the 10 members of the project Advisory/Training Team, all will gain sufficient understanding of the ecological approach to weed management to convey the essential paradigm shift to growers. At least 8 will co-present workshops to extension personnel. All will use knowledge gained in the project in extension activities reaching a minimum total of 300 growers, and improve weed management on 30 farms during the lifetime of the project.

Target 2. Of 210 extension professionals who take the weed management workshops, 170 will answer an evaluation questionnaire, and of these 150 will perceive improved skill in ecologically based weed management. Ninety of these will have used that knowledge in extension activities.

Verification and assessment
Members of the project Advisory/Training Team will keep records of their use of the knowledge gained from the project in their work with farmers (e.g., newsletter articles, one-on-one advice etc.) from the time they first receive the draft manuscript. They will also note any related changes they perceive on the farms with which they have contact. At the ends of Years 2 and 3, the Project Coordinator will collect and compile these notes. In addition, at the beginning of year 3, they will answer a questionnaire to evaluate their level of knowledge acquisition.

Contact information will be collected from workshop attendees. At the workshops they will be asked to keep track of their use of knowledge gained through the workshop and reading of the manual. During the latter part of Year 3, they will be contacted to determine (i) whether they perceived improvement in weed management skills as a result of the workshop or manual, (ii) the extent to which they used the information in their work, and (iii) how many farms they know of that changed weed management practices as a result of their advice. Contact will be first by e-mail, with telephone calls to non-responders.


Note that the project is currently midway through project year 2. Consequently progress toward milestones for years 1 and 2 are discussed below.

Milestone 1:
“The authors will complete the draft of the core of the manual, and the project Advisory/Training Team will review it and provide feedback. (2nd half of Year 1).” Five of the ten project Advisory Training Team members have returned comments on the draft manual. The remaining five have read the draft manual and are working on comments.

Milestone 2:
“The Project Coordinator and members of the Advisory/Training Team will conduct three training workshops for extension personnel on the principles and implementation of ecological weed management. Copies of the draft manual will be distributed at these workshops and feedback solicited. These workshops will be attended by a minimum total of 70 people. (Year 1).” One workshops on weed management was given for extension personnel in Lewiston, ME, 26 March, 2007 with 20 attendees. In addition, the talk on weed management used in the workshop was given to farmers in Hagerstown, MD, on 13 Jan. Thirty eight people attended, 3 of whom were extension educators. Many of the growers attending were leaders in the organic/sustainable agriculture community and can be expected to use the information to aid other growers.

Milestone 3:
“The authors will revise the draft based on comments of the Advisory/Training Team, and will complete descriptions of ecology and management of individual species. The revised manual will be reviewed by the Advisory/Training Team. (Year 2).” The manual’s authors are currently in the midst of revising the draft based on advisor comments. Two case studies were written for farms in the Northeast and these were reviewed by the farmers in question and the case studies revised based on their feedback. Additional case studies from other regions are waiting on information and contacts from the Sustainable Agriculture Network (the publisher). Nine additional species/species group entries were written, covering 14 weed species.

Milestone 4:
“Project leaders and members of the Advisory/Training Team will conduct 5 additional training workshops for extension personnel on the principles and implementation of ecological weed management. Copies of the draft manual will be distributed at these workshops and feedback solicited. These workshops will be attended by a minimum total of 140 people. (Year 2).” So far during Project Year 2 we have conducted two additional workshops: Ocean City, MD, June 20, 2007 with 10 attendees, and Ithaca, NY, Nov. 15-16 (given in two sessions) with 24 attendees. In addition, the talk on weed management used in the workshop was given to15 students in an organic farming class at Cornell University on 15 Sep., 2007. Many of these students are likely to go into extension or become leaders in the farming community. An additional two workshops are planned for the last half of Project Year 2.

Impacts and Contributions/Outcomes

Evaluations of the workshop have been highly favorable. Seventy six percent of participants indicated that the workshop substantially or very substantially increased their knowledge of weed management. Eighty six percent indicated that their ability to solve weed problems was improved. Sixty six percent indicated that they would definitely use the manual in their extension work and an additional 32 percent indicated that they would probably use it (a total likely use rate of 98%).

Seventy copies of the draft manual were distributed: 10 to project advisors, 54 to workshop attendees and an additional 6 to extension personnel who were unable to attend a workshop but requested a manual for use in their work.

Four advisors have helped lead workshops for extension educators (see performance target 1). Only two of the advisors kept a log of their weed related extension activities, but several others provided rough estimates or anecdotal accounts of their activities. We are working to improve record keeping for next year. One advisor estimated he had several hundred contacts about weed management with over 150 people. Most of these were one-on-one consultations. He indicated that when growers can obtain a copy of the manual, this will facilitate his ability to advise them. Another advisor gave two talks specifically on ecological weed management to a total of 128 attendees, and included weed management information in several additional talks. These two advisors alone have already come close to reaching the project performance target of reaching 300 growers during the life of the project. Other advisors had fewer contacts, but felt they had had a substantial impact on improving weed management on specific farms. In one case, a member of the advisory team had repeated contacts regarding weed management with a certified crop advisor who was assisting in the transition of several thousand acres to organic production. He felt that these consultations had very substantially improved weed management on this farm.


Emily Brown-Rosen
Organic Research Associates
PO Box 5
Titusville, NJ 08560
Office Phone: 6097378630
Richard Kersbergen
Extension Professor
University of Maine Cooperative Extension
Waldo Co. Extension Office
992 Waterville Rd.
Waldo, ME 04915
Office Phone: 2073425971
Eric Sideman
Director of Technical Services
Maine Organic Farmers and Gardeners Association
31 Anson Rd.
Greene, ME 04236
Office Phone: 2079464402
Steve Gilman
130 Ruckytucks Rd.
Stillwater , NY 12170
Office Phone: 5185834613
Klaas Martens
Lakeview Organic Grains
1443 Ridge Rd.
Penn Yan, NY 14527
Office Phone: 3155369879
Laura Hunsberger
Extension Educator
Maryland Cooperative Extension
PO Box 219
Snow Hill, MD 31863
Office Phone: 4106321972
Abby Seaman
Senior Extension Associate
Cornell Cooperative Extension
IPM Program Office
PO Box 462
Geneva, NY 14456
Office Phone: 3157872422
Antonio DiTommaso
Associate Professor
Cornell University
Department of Crop and Soil Sciences
903 Bradfield Hall
Ithaca, NY 14853
Office Phone: 6072544702
Todd Mervosh
Assistant Scientist
The Connecticut Agricultural Experiment Station
153 Cook Hill Rd.
PO Box 248
Windsor, CT 06095
Office Phone: 8606834984
Ed Stockman
Organic Extension Educator
Northeast Organic Farming Association-Massachusset
131 Summit St.
Plainfield, MA 01070
Office Phone: 4136345024
Scott Guiser
Extnesion Agent
Pennsylvania State Cooperative Extension Service
1282 Almshouse Rd.
Doylestown, PA 18901
Office Phone: 2153453282
Mark Schonbeck
Virginia Association for Biological Farming
439 Valley Drive NW
Floyd, VA 24091-2432
Office Phone: 5407454130