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Research needs: Weed research a result of producer interest

by Wyoming Livestock Roundup

Powell – On July 17, the Powell Research and Extension Center hosted its field day to highlight the research projects being conducted at the 220-acre facility, hosting 100 area producers and community members, as well as UW President Tom Buchanan.
    “This is the 150-year anniversary of the Morrill Act, which created the land grant system. The University of Wyoming is the only land grant school in the state of Wyoming,” commented Buchanan at the event. “A big part of the reason why UW has such a strong and growing commitment to agriculture and will continue to have that commitment into the future is because of the Morrill Act.”
    At each of the experiment stations across the state that operate in conjunction with UW researchers, a variety of projects are conducted annually to address the needs of agriculture in their regions.
    “While we were sitting in a regional crop improvement meeting, the growers asked for information on incorporating chemical weed control methods into the soil,” explained Director of the Wyoming Agricultural Experiment Station Bret Hess.
Weed interests
    As a result, Andrew Kniss, UW plant sciences professor, tackled a study titled Evaluation of Mechanical Incorporation Equipment for Dry Bean Herbicides. The study was funded by the Wyoming Crop Improvement Association and the Wyoming Seed Certification Service.
    “This study looks at mechanical incorporation methods,” described Kniss. “One of the issues we have with dry bean production, particularly in this area where we don’t have a lot of overhead irrigation, is that we have to utilize mechanical incorporation. We have to stir the herbicide into the soil in order for it to be effective.”
    “In this study we applied Eptam plus Sonalan over the entire study,” explained Kniss. “We came in with different kinds of incorporation equipment. We also utilized one pass of that incorporation equipment versus two passes.”
    Kniss added that, if only one pass of equipment to incorporate herbicide into the soil is necessary for effective weed control, producers would be able to save money.
    A roller harrow, Vibra Shank with sweeps, Vibra Shank with points, S-tine and disk were utilized to incorporate the pesticide to approximately four inches deep.
    “Primarily, we are interested in hairy nightshade as our key weed species,” commented Kniss, noting that the field exhibits a high population of sunflowers in its second year.
    The first year of the study also evaluated control of redroot pigweed, green foxtail and wild buckwheat.
Initial results
    While the study results published in this year’s Wyoming Agriculture Experiment Station Field Days Bulletin are only preliminary, Kniss noted that weed control was worst when a roller harrow was used to incorporate herbicide.
    “Two passes of the incorporation implement only increased weed control significantly more than one pass when the roller harrow was used,” wrote Kniss. “However, there was a slight trend for better redroot pigweed control with two passes compared to one pass of several implements.”
    In general, the Vibra Shank with points tended to control pigweed better than the implement with sweeps, and Kniss speculated that the effect was probably do to the difference in soil mixing due to the depth or action of the implement.
    Only very early data has been collected for the second year of the study.
    “The results that we are seeing from this year’s study are not necessarily matching up with last year,” added Kniss. “That is one of the reasons we do multi-year research here at the experiment centers.”
This year
    In the second year of the study, Kniss said, “We didn’t get very good weed control in these plots, but as part of weed research, that is part of the game. We can’t tell what works and what doesn’t unless we start with some really weedy fields.”
    By allowing the field to go to seed in 2011, the first year of the study, and additionally seeding the field with nightshade prior to planting, Kniss achieved a “weed jungle.”
    Kniss speculated that the decreased efficacy of weed control in the second year of the study may be a result of two factors. Increased weed density and decreased moisture during the spring likely affected efficacy of herbicide.
    “This year, I think we have a good population of weeds to look at, so we will be able to get some really good data this year,” noted Kniss. “We also seem to have better weed control when we have some overhead incorporation in addition to the mechanical corporation.”
    “After this year, we will know a lot more,” he added. “We will look at the second pass and see if there are any general trends as far as recommendations for which type of mechanical equipment to use for weed control.”    
    The second year of the study will also look at yield data to address competition of the beans and weed populations.
    For more information on this study, contact Andrew Kniss at or 307-766-3949 or view the Wyoming Agriculture Experiment Station Bulletin at Saige Albert is managing editor of the Wyoming Livestock Roundup and can be reached at

Spiering emphasizes the ‘ships’
Powell – Powell Research and Extension Center Advisory Board member Kelly Spiering addressed participants during a tour of the facility of July 17, mentioning that, without relationships between the center and its constituents, resulting research was less valuable.
    “The buzzword we should be thinking about is ‘ships,’” commented Spiering. “That means friendships, relationships and partnerships. Relationships are the keys to success.”
    Spiering added, “If researchers just do research without thinking about the people that it is going to affect, it loses value. The benefit that they can provide in the larger scope makes the research valuable for all.”
    In forming relationships with the public, Spiering added that the Powell Research and Extension Center could be more productive and a more valuable asset for producers in the area and across the state.

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