Our Mission

To protect natural resources from the threats of invasive species.


Our Vision

​Healthy and resilient native ecosystems in the upper Gallatin Watershed.

Our Story

The alliance began in 2004, when two people witnessed spotted knapweed taking over Gallatin Canyon and decided to take action. Today, our organization is celebrating 16 years of positive impacts on the lands we love.

The Challenge

"Resource managers everywhere recognize that invasive non-native species are the biggest threat to the integrity and function of terrestrial and aquatic environments. The Gallatin watershed is no exception. Over several decades of resources management, I have seen landscapes recover from every type of calamity but I have never seen a landscape recover from the introduction of invasive species.” ~John Councilman, board chair, retired US Forest Service Resource Assistant, Custer-Gallatin National Forest

Important Work

Our project area encompasses some of the most ecologically and economically important resources in the state, providing vital habitat and water for plants, wildlife, and the people who live and recreate in the area. The Alliance works to address and mitigate the impacts of human activity upon natural resources to ensure that what we love so much about this place is not destroyed by our pursuit to experience it.


Annual Reports

Learn more about

what we do!

2020 Annual Report

2019 Annual Report

2018 Annual Report

2017 Annual Report

2016 Annual Report

2015 Annual Report

2014 Annual Report

2013 Annual Report

2012 Annual Report

2011 Annual Report

2010 Annual Report


Gallatin Invasive Species Alliance Board

The individuals who serve on the board represent a combined 160 years

of involvement and expertise in natural resources, horticulture, and invasive species.

  • John Councilman


    John is a recent retiree from the Custer Gallatin National Forest where he worked for nine years on the Bozeman Ranger District. A graduate of the University of Idaho, he had a 36 year career with the Forest Service with most of that time spent working in forest management as a silviculturist and forest management specialist in Idaho. He has also managed wildlife, range, minerals, soils, hydrology and noxious weed programs. He is a proponent of landscape ecology and progressive forestry techniques. John enjoys many outdoor activities with his wife Kim who is lead project scientist for a non-profit conservation organization.

  • Mike Jones

      Vice Chair

    Michael Jones was fortunate to grow up in Yellowstone National Park, where he developed a great appreciation of wild places. After earning a B.S. in Fish and Wildlife Management and an M.S. in Fisheries Ecology, Michael began his career in noxious weed management as a seasonal weed control technician working for the U.S. Fish and Wildlife Service. Michael’s seasonal work captured his interest in invasive plant management as an effective wildlife conservation tool, joining the Gallatin County Weed District in 2010 as the Assistant Coordinator / Foreman.  When he is not fighting weeds Michael can be found fly fishing, rafting, or exploring the back-country. 

  • Katie Coleman


    Katie Coleman has lived in Big Sky since 1999 and worked in a variety of fields including the food service industry, education, non-profit management, and currently an Administrative Assistant at Hammond Property Management. Her love of the outdoors and the Greater Yellowstone Ecosystem has drawn her to the Alliance Board where she looks forward to contributing to the education of the community regarding noxious weed management. When not working, you can find Katie, her husband Tim and their dog Uli cooking, camping and playing outside as much as possible.

  • Don McAndrew

    Don McAndrew worked for 34 years with the Natural Resource & Conservation Service as an Engineer, Hydrologist, and Director of Operations, followed by 20 years as a realtor specializing in farm, ranch, and recreation real estate. Don has served as a volunteer on the Big Sky Planning and Zoning Board, Gallatin Conservation District, and the Northern Rockies RC&D. Don is a property owner in Big Sky and is a founding director of the Alliance. 

  • Larry Holzworth

    Larry Holzworth has had an extensive career working for the Natural Resources Conservation Service as an Agronomist, Plant Materials Center Manager and Plant Materials Specialist for 37 years. He worked with landowners on soil and water conservation, reclamation of disturbed lands, grazing land improvement and weed suppression projects in CO, AZ, UT, NV, MT & WY. After his official retirement, he has served on the board of the Gallatin Invasive Species Alliance since 2008, member of the Gallatin County Weed Board, is a CES field inspector for Weed Seed Free Hay and Certified Seed field inspector for the Montana Crop Improvement Association. In his free time he enjoys spending time with his family exploring the outdoors and working on home and land improvement projects.

  • Lorri Lagerbloom

    Lorri Lagerbloom resides in Big Sky with her husband and stepson. She moved to Montana from upstate New York, where she had worked as a horticulturalist preserving native plant communities. Lorri is an artist, represented by Gallatin River Gallery in Big Sky’s town center. Her beeswax encaustic paintings depict the Western landscape and bird’s native to Southwest Montana. She is an avid skier, wildlife lover, naturalist, and environmental activist. 

  • Danielle Jones

    Danielle Jones has a master’s degree in Biology from Montana State University and has been working in the Natural Resources field for over 20 years.  Her interest in noxious weeds first began while pulling spotted knapweed on Mount Sentinel as a student at The University of Montana, where she earned a bachelor’s degree in Wildlife Biology.  She lives in Manhattan with her family.

  • Krisy Hammond

    Krisy moved to Big Sky the fall of 1993, working for dude ranches and outfitters, including Lone Mountain Ranch for over twenty years. It is here that she met her husband, Scott, and the rest is history. With their two kids, Chloe and Gus, dogs, cats and horses, they enjoy a busy and fulfilling life hiking, nordic skiing, riding horses and pulling weeds all along the way. A passionate volunteer, Krisy lends her talent and time to the Montana Wilderness Association, Habitat for Humanity, Windhorse Equine Learning and various other groups. Although she went to school for elementary education, her passion for wildlife biology and love for the native grasses and flowers of Montana has led her to join the board of the Alliance.

  • Jennifer Mohler

      Executive Director

    Jennifer Mohler is a resource conservationist and executive director for the Gallatin Invasive Species Alliance. For over 20 years, Jennifer has worked with a diverse group of public, private, and non-profit entities to conserve natural resources by promoting sustainable land management practices. In her free time, she’s trains and competes in 3 day eventing with her horses, is an avid gardener, and enjoys hiking the trails with her husband and dogs.

Why Should I Care?


The Gallatin Invasive Species Alliance's project area encompasses some of the most ecologically and economically important resources in the state. The Gallatin River is a centerpiece within the Greater Yellowstone Ecosystem and provides vital habitat and water for plants, wildlife, and the people who live and recreate in the area. Those of us who live in this area of Montana choose to do so because of the abundance of recreational opportunities, the amazing and unique wildlife that resides here, and the stunning beauty of the landscape.


The effect of noxious weeds on plant diversity and ecology can cause the loss of wildlife habitat. Infestations of noxious weeds displace native plants and change water flow and availability. Spotted knapweed populations alone reduce available winter forage for elk by 50 to 90 percent. Noxious weeds also increase soil erosion and soil sedimentation, which can have a devastating impact on fishery populations in our local rivers and streams. Runoff is 1.5 times higher and sediment yield was found to be 3 times higher on areas dominated by spotted knapweed than on areas with native grasses.

Learn more here:  Why Should I Care?

Leveraging Assistance Through Partnerships

The Alliance spends significant time and effort toward its goal of coordinating efforts and working cooperatively with various federal, state, and local agencies in invasive species education and control within in the project area.

Personnel from partner organizations assist with community events, education and outreach, noxious weed treatments, logistical support, and funding. Their commitment and willingness to participate are major contributors to the successes the Alliance has achieved over the past 14 years.

Our Partners

Beehive Basin Brewery

Big Sky Community Organization

Big Sky Landscaping

Big Sky Owners Association

Big Sky Resort

Big Sky Resort Tax

Big Sky Water & Sewer

Bridger Brewing Company

Bucks T-4

Coffee Pot

Custer-Gallatin National Forest

Dept. of Natural Resources and Conservation

East Slope Outdoors

Jack Creek Preserve

Gallatin Canyon Women's Club

Gallatin County

Gallatin County Conservation District

Gallatin County GIS Department

Gallatin County MSU Extension

Gallatin County Weed District

Gallatin River Task Force

Gallatin Valley Land Trust

Gallatin Watershed Council

Great Bear Native Plants

Greater Yellowstone Coordinating Cmte

Historic Crail Ranch

Madison County Weed District

Madison Gallatin Trout Unlimited

Moonlight Basin

Moonlight Community Foundation

Montana Conservation Corps

Montana Department of Agriculture

Montana Department of Transportation

Montana Fish, Wildlife and Parks

MT Noxious Weed Education Campaign

Montana State University

Montana Weed Control Assoc.

Montana Weed Control Association

Montana Wilderness Association

Multiple Big Sky HOA’s

Mystery Ranch

Natural Resources Conservation Service

One Montana

Ophir School

Rad Bikes

Rotary Club of Big Sky


Spanish Peaks Community Foundation

Spanish Peaks Mountain Club

Yellowstone Club

Yellowstone Club Community Foundation

Westscape Nursery

Wild Sheep Foundation

© Copyright 2021 by

Gallatin Invasive Species Alliance

Tel: 406.209.0905

Email: info@gallatinisa.org