Working together to strengthen and support noxious weed management efforts in Montana.


MSU Report for the Montana Noxious Weed Trust Fund Advisory Council

Wednesday, June 19th, 2013


This report for the Montana Noxious Weed Management Advisory Council was assembled in compliance with the Montana Noxious Weed Trust Fund Act and Administrative Rules which require an annual report from the Montana Agricultural Experiment Station and Montana State University Extension Service on current projects and future plans. This report is a compilation of major weed science research and education activities conducted by MSU over the past three years and includes highlights of funded Montana Noxious Weed Trust Fund grants as well as comprehensive reporting of all weed science research products and education funding and activities.

Montana Noxious Weed Trust Fund Projects 2010–2012

  • Biological Control of Common Tansy and Oxeye Daisy, Jeff Littlefield
  • Biological Control of Invasive Hawkweed and Tansy Ragwort, Jeff Littlefield
  • Biological Control of Russian Knapweed, Jeff Littlefield
  • Biological Control of Whitetop and Perennial Pepperweed,Jeff Littlefield
  • Can Biological Control and Targeted Sheep Grazing be Integrated to Suppress Spotted Knapweed?, Jeff Mosley
  • Cheatgrass Ecology and Integrated Management, Jane Mangold
  • Continental Divide Invasive Weed Barrier Zone, Kim Goodwin
  • Establishing and Monitoring Insectaries for Yellow Toadflax Biocontrol, David Weaver
  • Herbicide Resistance Extension Information for Montana Producers, William Dyer
  • Identifying and Testing Candidate Agents for Russian Olive Biocontrol, David Weaver
  • Implementing EDRR in Montana Using the INVADERS Database, Jane Mangold
  • Integration of Pathogens, Sheep, and Herbicides to Manage Cheatgrass, Fabian Menalled
  • Missouri River Watershed Coalition Coordination, Elizabeth Galli-Noble
  • Rangeland Revegetation Revisited, Jane Mangold        Saltcedar Effects on Mycorrhizal Fungal Communities and Screening of Native Species for Restoration, Erik Lehnhoff
  • Tall Buttercup Ecology and Integrated Management, Jane Mangold
  • Weed Free Borders Protection Program, Kim Goodwin
  • Weed Management Certification Program, Jane Mangold
  • Weed Seedling Identification Guide, Jane Mangold

Download a copy of the complete report 2013 MSU Annual Report to the MNWTF

How do I Winterize my Equipment and Protect my Chemicals?

Monday, November 5th, 2012


Here are some great publications to help you prepare for winter

Montana State University Integrated Pest Management program’s bulletin about winterizing your equipment and cold storage of chemicals.  Download the MSU bulletin.

Missoula County’s Summer Issue of Healthy Acres

Thursday, June 28th, 2012


Missoula County Weed District produces an online magazine called Healthy Acres.   The summer issue is now available to download.

Of special interest to weed warriors is a profile on Purple Loosestrife, and information about the pesticide container recycling.

DuPont is implementing a voluntary suspension of sale of Imprelis® herbicide

Monday, August 8th, 2011


The following information is all from the DuPont website.   We encourage you to visit their site for the latest information about Imprelis.

DuPont is implementing a voluntary suspension of sale of Imprelis® herbicide, and will soon be conducting a product return and refund program for the product. This action is consistent with our ongoing discussions with, and response to, the Environmental Protection Agency.

If you are an Imprelis® distributor or customer, please do not take any action regarding this product return and refund program until we contact you with additional information.

DuPont ™ Imprelis® Hotline 866-796-4783

If you are a lawn care professional, property owner or manager, or golf course manager or owner, we encourage you to call our hotline to report damage to trees that may be related to Imprelis®.

If you are a homeowner, please call with questions or concerns.

This letter was posted on the DuPont website:

Dear Turf Management Professional:

I am writing to update you on the situation with Imprelis® herbicide.

First and foremost, I want to underscore DuPont’s commitment to our customers’ satisfaction and to responsible stewardship of our products. We sincerely regret any tree injuries that Imprelis® may have caused, and will work with you to promptly and fairly resolve problems associated with our product.

Since we sent you our original letter, we have reached out to those of you who have reported concerns, both to gather information and to determine how best to work with them to address those concerns.

Based on our ongoing review, we have observed tree injuries associated with Imprelis® primarily on Norway spruce and white pine trees. The reports of problems are concentrated in a geographic band that includes Minnesota, Michigan, Indiana, Ohio, Pennsylvania, New Jersey and Wisconsin. While most properties treated have had successful weed control, we are committed to continuing to work with every customer who has experienced Imprelis-related problems.

If you have concerns or issues with our product, we would like to hear from you. To make it easier to report problems and have them resolved as quickly as possible, we are:

  • Engaging 20 independent, certified arborist companies to work with you and evaluate your claim.

  • Launching a website,, to carry the latest information about Imprelis® and make it easier for you to report problems. We urge you to go to the website for more information and to check back frequently for updates.

  • Establishing a toll free hotline to take all reports of problems from lawn care professionals, property managers and owners, and golf courses, and to handle any questions and concerns.

  • The hotline will go live on Monday, August 1. The number will be made available on the website.

  • Continuing to work on this issue with the Environmental Protection Agency, state regulators and university extension specialists.

We ask for your cooperation while we work to rapidly address this matter and institute processes and procedures to remedy your situation. It is our goal to have a claims process set up as soon as possible.

Thank you for your patience and ongoing support of DuPont Professional Products as we work through this together.

With regards,

Michael McDermott
Global Business Leader
DuPont Professional Products

Learn About Calibration for Using Herbicides

Thursday, August 19th, 2010


One of the most important things that can be done when using herbicides is making sure you are spraying the right plant and you are using the right amount of herbicide.  Learning how to use the right amount of herbicide is called calibration.

There are many ways a person can learn about calibration.

  • Contact your local weed coordinator or extension agent.
  • Attend a Private Applicator’s Class in your area.
  • Use a combination of print and video materials available.

The following are some of the print materials available.  We have provided links or you may contact your extension agent.

MWCA helped to underwrite this short video that demonstrates calibration of equipment.  We have broken it down in to 6 steps.

Chapter 1 Importance of Calibration

Chapter 2 Equipment & Pre-Calibration Check

Chapter 3 Understanding Calibration

Chapter 4 Calibrating Backpack Sprayer and Handline

Chapter 5 Calibrating Using the Strip Method

Chapter 6 Adding Pesticide to Your Tank

MSU Extension also has a DVD available for purchase on their website. There is also information on the MSU Webpage on Calibration.

Bear Trap Success Story

Wednesday, June 23rd, 2010


In April of 2001 a float trip down the Madison River was conducted involving members of the BLM, the Montana Wilderness society, Madison County, U.S. Forest Service, the Greater Yellowstone Coalition, Gallatin County and other interested individuals. They determined that due to the size, density and location of the current infestations, that eradication was no longer an option but that a long term plan of control and containment would be more practical and cost effective. With members of the original group plus a Dow AgroSciences representative and others knowledgeable in noxious weed control a second float trip was conducted in August to help devise a plan of action.

Weed control was initiated in the fall of 2001 using both biological agents and herbicide. The biological control was released in the more inaccessible areas above the river and above the hiking trails, while herbicide was used along the trails and from the trails to the river, where public use is the highest. Herbicide application was done as a joint effort between the BLM and the Madison County Weed Board with joint spray days being held twice yearly, one in the spring and the other in the fall. After the first year of treatment we were surprised at how the native grasses came back and became fairly competitive with the knapweed. In 2002, 2003, and 2004 a private contractor treated the road leading into the trailhead and any of the trails that couldn’t be covered during the joint spray days. Starting in 2005 the BLM hired a crew of two sprayers that would take over the role of the private contractor. A minimum of three float trips a year were scheduled in order to gain access to some infestations of Leafy Spurge that are inaccessible by land.

To date the project has met with great success. The size and density of the noxious weed infestations has been reduced dramatically with the only problem being the re-infestation of some of the treated areas by cheatgrass. Beginning in 2010 we hope to get the original group together again to determine what our strategy for the next ten years will be and how we will handle the re-vegetation of some of the areas infested by cheatgrass.

Canal Success in Valley County

Wednesday, June 9th, 2010


Leafy spurge is along fenceline and in the pasture

Leafy spurge is along fenceline and in the pasture

The Valley County Weed District has teamed up with the Glasgow Irrigation District since 2002 to control noxious weeds on 46 miles of main canal and 44 miles of lateral canals. Think about noxious weed seeds being spread by a water system 90 miles long. Wildlife and domestic animals have been spreading seeds from near that water source. Also, think about walking through a solid stand of mature Canada thistle for 1/8 mile! Not a pleasant thought! That was the situation in 2002 on the irrigation canal system in Valley County. The Glasgow Irrigation District and the Valley County Weed District decided to do something about these noxious weeds. Now in 2009, they are under control and the canal system, overall, is in good condition, thanks to financial funding through the Montana Noxious Weed Trust Fund Grant Program. The canal system has 46 miles of main canal from Vandalia Dam in the west and flows east to Nashua. There are 19 lateral canals (44 total miles) that also were infested in areas with leafy spurge that are under control. For anyone who has ever been involved with noxious weed control, the reality is that the work is never truly done. However the ranchers and farmers who use the canal system have seen great results and can be confident that their land and crops will not be lost or severely damaged by infestations of noxious weeds.

Leafy spurge was treated with Tordon22K and 2-4D

Leafy spurge was treated with Tordon22K and 2-4D

For more information contact Rick Stellflug, Valley County Weed Coordinator

What is sprayer calibration and why do I need to calibrate my sprayer?

Friday, October 23rd, 2009


The objective of calibration is the same no matter what kind of sprayer you are using, to apply the correct amount of chemical to do the job.  All pesticide labels tell you how much you should be applying.  If you apply too much chemical you may impact other plants and resources that you do not want to.  If you apply too little chemical you may not get the results you want.

MWCA has a web page with videos and reference materials to help demystify calibration.