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Philosophies in Extension weed management

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Upated December 23, 1997 -- Information needs for weed management was discussed in a symposium held at the 52nd North Central Weed Science Society meeting held in Lousiville, Kentucky on Dec. 8-11.  The symposium was organized by Richard Proost and his colleagues at the University of Wisconsin.  Three extension specialists provided their philosophy on developing an effective extension program in weed management.  Due to the interest in this topic shown at the symposium, abstracts of the presentations are presented below.

INFORMATION NEEDS FOR WEED MANAGEMENT: ASSESSING OUR TRADITIONS. Richard T. Proost, Chris M. Boerboom, David E. Stoltenberg, Larry K. Binning and Peter Nowak, Senior Outreach Specialist, Associate Professor, Associate Professor, Professor and Professor, Nutrient and Pest Management Program, Horticulture, Agronomy, Rural Sociology, University of Wisconsin, Madison, WI 53706

The transfer of research information to farmers plays the key role in the adoption of agricultural technologies. In the past, the Extension service was the primary disseminator of agricultural information to farmers.  Today, the private sector has surpassed the extension service in providing such information. This situation has raised a number of concerns that this symposium will address. This symposium is composed of two panels discussing two aspects of weed management information transfer. The first, "Philosophies in Extension Weed Management Information Transfer: Information Type and Target Audience", examines the past, present and future roles of extension and outreach in weed management information transfer. This panel consists of three extension weed scientists and one rural sociologist and will address who their primary audience is, why that audience was targeted, and what type of information they have been transferring and why. The second aspect, "Information Needs in Weed Science: From Manufacturer to Farmer", explores the flow of information within the private sector. Panel members include a representative from the chemical industry, a national cooperative, a crop consulting firm, and a university. Their charge is to describe their primary audience, why that audience is selected, the type and source of their current information, and what role Extension should have in weed management. This symposium is intended to allow participants to do an introspective evaluation of their educational programming efforts.


Binning, Professor, Horticulture, University of Wisconsin, Madison, WI 53706


The philosophy I was asked to present (not my own) assumes that a weed management program is synonymous with herbicide use. Producers know "How"
and "When" to cultivate, its' not my job to remind them of the importance.   As an extension professional, I have a finite amount of time and as such, Ihave to spread the word to affect the most acreage in an expeditious manner. Thus programming efforts are directed to the large, progressive producers. Because herbicides are the most commonly used pesticide, and covers the largest land mass, producers need to know how to use these products. My job is to tell them. Herbicide efficacy trials are the best
way to accomplish this task. The industry advertising does not help producers decide what to use. Hornets pulling weeds out of a field, Raptors peering out of a fence post, or farmers repeating "eight bucks back" is hardly the type of information that producers can use to make intelligent product use decisions. However, herbicide efficacy trials will provide producers with comparison data that helps them to make product decisions. Producers want and need a certain amount of handholding when it
comes to herbicide decisions. The information I generate and transfer to them guides them through the process of herbicide selection, proper use rates, tank mixtures and carryover concerns. Much of this information is generated on agricultural research stations, however, some comes from strip trials conducted with producers. I make use of printed materials, demonstrations, fields days, and electronic methods to deliver information.   I previously stated, I target the large producers, i.e. those in the 20/80
group. (The 20/80 group is the top 20 percent of the producers that produce 80 of the product.) I also target the dealer distributors, corporate agronomists, and fieldmen as they are looked to by the producer to provide them the needed information. Again, the reason I target this group is that they are responsive and can effect change on the greatest amount of acreage. Why wouldn't I target them? So to reiterate: my basic
program and assumptions are that weed management is chemical based; producers need and want unbiased regionally tailored information; both the producer and supplier are the users; the best information is obtained through efficacy trials; and that the information must be good and on target because that is what the producers are asking for.


PHILOSOPHIES IN EXTENSION WEED MANAGEMENT INFORMATION TRANSFER: INFORMATION TYPE AND TARGET AUDIENCE. Jeffrey L. Gunsolus, Associate Professor, Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108.

The coordinators of this symposium have asked me to present a short response to the following two questions: 1. Who is your primary audience and why? 2. What type of information have you been transferring and why? In general terms, my answer to question number one is brief. Within the context of my corn and soybean weed management educational programs I differentiate only between two primary audiences; crop producers and information disseminators. Crop producers are, of course, farmers who are actively involved in the production of corn and soybeans. The information disseminators are a much more diverse group that includes the following people: crop consultants/advisors, agrichemical industry representatives, agricultural educators and seed company representatives. I believe the information disseminator group is a critical group to reach because many farmers go directly to them for advice.

To answer the question of what type of information is being transferred to these two primary audiences I will start with defining the primary objective of my extension education and applied research program. My primary objective is to develop a more sustainable corn and soybean production system by teaching the principles of safe, effective, and cost-efficient weed management. I see the diversification and integration of weed management systems as a cornerstone to achieving this objective.

In defining what type of information to transfer it is important to note that in my objectives statement I emphasized the "teaching of principles" of weed science and crop management. It is my belief that as an educator I should approach even very applied technology based problems (e.g. herbicides) from a principles perspective. The rational for this is that due to the complex nature of crop systems and the diversity of individual cropping enterprises it is impossible for me to address the multitude of individual grower weed control needs and objectives. Therefore, by teaching at least a simplified version of the science behind weed science the individual grower or information disseminator will be better able to tailor a technology transfer issue to their particular situation. It is my objective, no matter how ideal, to have the audience understand at least some of the science behind weed management so that they can better tailor their decisions to a site-specific time or location.

To illustrate my point I will use the example of Roundup Ready technology. Besides the need to make the grower aware of the basic aspects of what the Roundup Ultra label and agribusiness guidelines are I believe it is important to make the grower aware of several other key points. These points would include: a discussion about residual versus non-residual herbicides, weed emergence periods, rate of weed growth, and critical periods of weed control. An understanding of these key points will increase the probability of successful adaptation of this new technology.

The key to teaching principles of weed science in such a technology based area of crop production is to keep the examples that you are using focused on real-life situations that the crop producer or information disseminator can relate to. In order to insure this type of relevancy to the audience, a group of us at the University of Minnesota have formed a statewide weed management team whose objective is to focus on evaluating weed management systems and to make sure that specific regional and site-specific producer concerns are addressed. This team currently is composed of two branch station Ph.D.’s, one technician each at three branch stations, one Crop Pest Management Specialist each at three locations, and myself. We are in the process of adding several Extension educators.

The advantage of the weed management team is that the members represent growers from differing regional climactic and weed spectrum areas of the state. Also, it is much more likely that a local crop producer will approach someone in their own cropping region with a particular problem than they would contact someone with a state-wide focus. Therefore, we feel that the weed management team helps to keep our extension educational programing relevant to the producer and information disseminator. Also, from an applied research perspective, the evaluation of weed management systems across these environmental gradients gives us some keen insights into the stability (i.e. risk) of various integrated weed management strategies. The weed management team has become a central point in our efforts to develop and transfer weed management information.


WEED SCIENCE EXTENSION: A BIOLOGICAL PESPECTIVE. Robert G. Hartzler, Associate Professor, Iowa State University, Ames, IA 50011.

As long as herbicides remain the foundation of weed management programs, there will be a need for extension to deliver information about these management tools. In fact, extension personnel must remain a viable source for herbicide information to maintain credibility with the majority of our clients. However, I believe changes in agriculture and land grant universities in the past 10 to 15 years have altered the role of extension in weed management education.

Extension previously was one of the few, if only, sources of unbiased information concerning herbicides. The maturation and consolidation of the agribusiness industry (herbicide manufacturers, seed companies, local supply outlets) has resulted in a large increase in the number of competent people able to provide herbicide information to growers. In addition, many extension specialists now have split appointments involving research and/or teaching. This has reduced the amount of time they have to ‘keep in touch’ with what is happening in the field on a daily basis. Finally, universities previously played a much more important role in helping industry evaluate new compunds and determining the appropriate market niche for these products. However, as the herbicide market has become more competitive, extension personnel often are not provided sufficient information nor time to evaluate new herbicides to base sound recommendations.

These changes have created an opportunity for extension to redirect their educational efforts more towards the principals of weed biology and integrated weed management, and therefore spend less time on herbicide evaluation and recommendation. The key to achieving acceptance of this information is packaging it in ways that allow clients to see the connection between fundamental biology/ecology and practical weed control. Although it may seem like a contradiction, the increased dependence on herbicides has increased the demand for this type of information. One consequence of the one-dimensional management programs being used in midwest agriculture is rapid shifts in weed populations. Providing clients with an understanding of the biological bases for these weed shifts prepares them to develop management programs that will provide adequate control of the new weed problems and reduce the likelihood of continued shifts in weed populations.

Several tools have been used at Iowa State University to disseminate information related to weed biology. At traditional extension meetings, weed biology information usually comprises 50 to 75% of the information presented, with the remainder of time spent discussing specific control tactics (herbicides, tillage, etc.). Several extension bulletins have been developed on topics such as herbicide resistance, crop-weed competition, weed seedbanks, and timing of weed emergence. These bulletins have been very popular, with several thousand copies being distributed each year. The demand for the weed biology factsheets exceeds that for our traditional herbicide recommendation bulletins. Posters, computer software programs, and a webpage have also been used to disseminate weed biology information. With the abundance of sources for herbicide information, I believe a niche exists for extension to provide the foundation of knowledge required to improve weed management systems used in agriculture. In the long run, this information should have a much greater impact on the decision making process of persons involved in weed management than simply providing information concerning specific control tactics, such as herbicide selection.

Prepared by Bob Hartzler, extension weed management specialist, Department of Agronomy, Iowa State University

For more information contact:
ISU Extension Agronomy
2104 Agronomy Hall
Ames, Iowa 50011-1010
Voice: (515) 294-1923
Fax: (515) 294-9985
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Common chemical and trade names are used in this publication. The use of trade names is for clarity by the reader. Inclusion of a trade name does not imply endorsement of that particular brand of herbicide and exclusion does not imply nonapproval.