Evaluation of Alfalfa Weevil (Coleoptera Curculionidae) Densities, Weed Abundance, and Regrowth Characteristics of Alfalfa Grazed by Sheep.

Evaluation of Alfalfa Weevil (Coleoptera Curculionidae) Densities, Weed Abundance, and Regrowth Characteristics of Alfalfa Grazed by Sheep.

Objectives/Performance Targets

1) General information

A. Project Title: Evaluation of Alfalfa Weevil (Coleoptera Curculionidae) Densities, Weed Abundance, and Regrowth Characteristics of Alfalfa Grazed by Sheep.

B. Subject Matter Area: Agricultural Systems

C. Funding: 1st Year: 47,335 2nd Year: 49,482 3rd Year: $0 Total: $96,817

D. Principal Investigator: E. Contract and Grant Office
Hayes B. Goosey, Research Scientist
Montana State University;
Dept. Animal and Range Sciences
Wool Lab, P.O. Box 172900;
Bozeman, MT 59717-2900
(406) 994-2012-work; (406) 994-5589-fax
hgoosey@montana.edu
Traci Miyakawa- Assistant VP of Research
Montana State University;
Office of Sponsored Programs
308A Montana Hall, P.O. Box 172470; Bozeman, MT 59717-2470
(406) 994-2381-work; (406) 994-7951-fax
TraciM@montana.edu

F. Producers:
John Helle
Helle Rambouillet
1350 Stone Creek Road
Dillon, MT 59725
Ph. (406) 683-6686
email: helle@bmt.net
John & Nina Baucus
Box 1683
Helena, MT 59624
Ph. (406) 458-9468
fax. (406) 458-0441
email: NONE Bob Lehfeldt
Box 175
Lavina, MT 59046
Ph. (406) 636-2731
email: levi@midrivers.com

G. Cooperators:
Cecil Tharp, Res. Assoc.
Montana State University
Dept. Entomology
Bozeman, Mt 59717-3020
Ph. (406) 994-5067
cthartp@montana.edu
Patrick G. Hatfield, Prof
Sheep Nutrition/Prod.
Dept. Animal and Range Sci.
Bozeman, MT 59717-2900
Ph. (406) 994-7952
hatfield@montana.edu
Sue Blodgett, Assoc. Prof.
IPM Specialist,
Dept. Entomology
Bozeman, MT 59717-3020
Ph. (406) 994-2402
blodget@montana.edu

Dennis Cash, Assoc. Prof.
Forage Crop Extension Specialist
Dept. Animal and Range Sci.
Bozeman, MT 59717-2900
Ph. (406) 994 5688
dcash@montana.edu
Rodney Kott, Prof
Extension Sheep Specialist
Montana State University
Bozeman, MT 59717
Ph (406) 994-5602
rkott@montana.edu
Duane Griffith, Assoc. Prof
Extension Ag Economics
210B Linfield Hall
Bozeman, MT 59717
Ph. (406) 994-2580
griffith@montana.edu

Montana Wool Growers
Aeric Reilly Sec/Tres
PO Box 1693
Helena Montana 59624
(406) 449-1330; 449-8606 (fax)
reillyaeric@hotmail.com

2) Summary

Traditional alfalfa weevil management relies heavily on the use of insecticides which target alfalfa weevil larvae. Insecticides lock producers into applications during years of high crop damage or high hay values.
Research conducted at Montana State University demonstrated that prescriptive sheep grazing can reduce alfalfa weevil populations up to 70%, prior to the growing season, without negatively impacting the quality or quantity hay. This represents a new paradigm in pest management by using strategic sheep grazing to prevent high alfalfa weevil populations and subsequent damage the growing season after grazing cessation.

3) Objectives

A) Compare various intensities (0-125 alfalfa weevil degree days) of sheep grazing (fall and spring), insecticides and a no-input control in a multi-farm study on:
a) alfalfa weevil larval numbers
b) alfalfa yield and nutritive characteristics
c) total biomass including alfalfa aftermath and broadleaf and grass weed species
d) change in soil in soil bulk density
Objective A will provide the PI and cooperators with the necessary data and knowledge to accurately and reliably address and implement the results of this and other relevant MSU research onto commercial farms and ranches. Can objective 1 be met with in the given timetable? YES. Responses to grazing systems are not always long-term; rather relevant to the grazing system and response variables as a whole. Changes in the response variables (a-d) have been documented, by the PI and others, under different grazing systems with similar timetables. If the proposed grazing will have positive/negative effects on these response variables, measuring these impacts is more than feasible within the given timetable. Additionally, this research will become part of an existing research/extension program aimed with a long term commitment to integrating sheep into farming systems. Preliminary research on these objectives has already been completed and published by the PI and additional research funds will be sought for years to come. Successful implementation of objectives 2-4 rely solely on accurate and reliable data derived from Objective 1.
B) Develop a specific fall and/or spring sheep grazing time-table, based on the alfalfa weevil degree day model, to maximize alfalfa weevil mortality.
Objective B is a desired outcome resulting from both objective 1 and previous research conducted by the PI. Producer input identified this objective as a critical component necessary to teach producers how to implement this grazing system. It is necessary that the PIs develop a grazing protocol which can easily and reliably adopted by alfalfa and sheep producers. Objective B incorporates scientists, extension personal, and producers. Incorporation of the alfalfa weevil degree day development with the grazing protocol will transform these results into a user friendly approach requiring minimal producer time commitments thus increasing acceptance. Implementation of objective B relies completely on addressing objective A. Once the necessary research is completed, addressing objective B will be completed with in the stated timetable.
C) Develop an economic model to evaluate long term cost-benefits of sheep grazing and insecticides in alfalfa production.
Development of a user friendly and readily accessible economic model, in the form of an excel spreadsheet, will increase producer acceptance. This economic model would be published for ‘free use’ online via the MSU web page. Farming and ranching are a business with a bottom line of profit. The economic model will be one additional piece of information to report to producers who are concerned about input costs and net return associated with sustainable practices. Objective C will include PI participation and a MSU agricultural economist.
D) Develop and conduct large, multi-farm demonstrations. Communicate results to producers, students, scientists, and the public on the advantages of incorporating prescriptive sheep grazing into alfalfa production systems.
Objective D includes scientists, educators, extension personal, and producers. Research sites on commercial scale operations will double as demonstration sites to increase producer acceptance and awareness. After research is completed and a grazing protocol is developed and accepted by both scientific and producer based personal intimately involved in the Objectives A and B, it will become the PIs top priority to disseminate the results to interested persons and create additional interest. Objective D will be reached through developing an extensive and well-rounded outreach/extension program starting locally, moving state wide, and then to the national level.

4) Accomplishments/Milestones

All field work was completed for this project in June 2009. The project work went smoothly with no major problems and data analysis and model development is completed. I am currently writing my dissertation on this project and will be defending my Ph.D on November 10th 2009. The grazing model will be validated in the spring of 2010 and it is anticipated that a publication in the Journal of Economic Entomology will be in press by mid-summer 2010.

5) Impact and Contributions/Outcomes

Extension and education has just begun. I have been invited to the North Dakota Lamb and Wool producer’s annual convention November 20th – 21st in Bismarck, ND to present the grazing model developed from this research. I will also be attending the Montana Wool Growers annual convention in Billings, MT to present the same results. These results will also be presented at the Montana Sheep Advisory Council meetings held November 2nd 2009, and published in their research bulletin. Total attendance at these three meetings is anticipated to be approximately 300 researchers and producers.
I have submitted a competitive paper to the American Sheep Industry for review and potential selection as first place (original research category). If selected, I would be invited to present these results at their annual convention January 20th, 2010 in Nashville, TN. This convention is attended by leading researchers and producers from around the United States. Finally, results will be presented on the Montana Sheep Institute: http://www.sheepinstitute.montana.edu/ .
Economic results are being integrated into an online ‘Decision Support’ program aimed at an interactive program where producers can evaluate the economics of grazing systems prior to implementing them into their operations. Preliminary results can be viewed at: http://www.montana.edu/softwaredownloads/software/Haying%20System%20Costs_Feb2008.xls

The program is not yet completed but it is anticipated that the final program, based on results of this research, will be producer available by February, 2010. A comprehensive final report will be submitted during 2010.

Collaborators: