Ask An Expert | How Does Removing Conifers Help Oregon’s Grouse?

May 31, 2016

Craig Foster works as a wildlife biologist in the 6,000 square-mile Lake District in southern Oregon, which has the second-highest abundance of sage grouse in the state. Photo by Lacey Jarrell, Klamath Herald and News. 

Ask an Expert: Craig “Fozz” Foster, Wildlife Biologist with the Oregon Department of Fish and Wildlife

What are the main threats to habitat for sage grouse in Oregon?

Western juniper encroachment is the number one threat for sage grouse in southern Oregon. Number two is exotic annual invasives, like cheatgrass and medusahead, which outcompete native vegetation, impacting the whole ecosystem. Number three is wildfire, which is linked to number two, since fires are exacerbated by invasive weeds.

When the landscape fills up with encroaching junipers, their roots occupy all of the space below ground, choking out native perennial shrubs and grasses. The only thing that survives in places with really dense conifers are annual invasive grasses—which circles back to problems two and three, compounding the threats to sage grouse.

How do you fix the problem?
A whole bunch of groups are involved in removing encroaching conifers to improve habitat in the sagebrush ecosystem. Together, we’ve treated over 63,000 acres for junipers. Our goal is to treat a chunk of land in a way that makes sense both ecologically and biologically. To do that, we try to set up projects that erase the property boundaries and take a landscape approach. That means finding funds to remove conifers on both public and private land, so you get a treatment that benefits the ecosystem, the wildlife, and everyone involved.

How does removing conifers help the birds?

Removing invading conifers opens up prime habitat for sage grouse.

Conifer encroachment in the sagebrush sea is the number one threat for sage grouse in this part of the country.

When you get out into our country here in Oregon, most of the juniper encroachment is in higher quality nesting and brood-rearing habitat, because that’s where the soil is deeper. We have a bunch of places where leks (sage grouse mating sites) have become inactive.

The science shows that sage grouse don’t like being hemmed in by trees. In the Warner Mountains, radiomarked birds won’t nest anywhere there’s more than 4% canopy closure—that’s only about three juniper trees per acre! Right now, we have places where there are 100 trees per acre.

What kind of results have you seen?
In the Lakeview District, we’ve been very fortunate to have the Bureau of Land Management and the Sage Grouse Initiative fund a long-term study to scientifically measure the response of sage grouse to conifer removal in the Warner Mountains.

We’re going into year seven of the study, and starting to see hens nesting in cuts completed five or six years ago. We’ve also gotten a really good growth response in the cuts from mountain shrubs, along with more native forbs and grasses in the cuts. This shows that the restoration work is positive for the birds and the sagebrush ecosystem.

Do you have tips for people working on large landscape conservation?
Look for a reason to say yes! It’s easy to say: “No, we can’t do that.” But if you continue to be a “no” person, you’re gonna miss opportunities. Learn how to listen and be objective.

Whether you’re working with livestock producers, plant people, or range conservationists, don’t be afraid to throw out ideas and then go try it. Most of the stuff we know about cutting juniper in this country is from trying something out, then walking back to it and saying: “This isn’t exactly what we wanted, so how do we make it better?”

Meet the Expert

conifer removal

After 34 years as a wildlife biologist in Oregon, Foster advises “just say yes” to start solving problems on the landscape.

Why did you become a biologist?
I knew way back in grade school that I wanted to work with wild critters. It started out for me by hunting and fishing. As I got older, I learned I could have a career as a wildlife biologist, and got my first job at 17 with Arizona Game and Fish.

What excites you about your work?
After 34 years, I still get excited by the challenge of working in nature. It’s very obvious once you go out into the sage steppe that this habitat is bigger than us, and is more complex than us. I love the challenge of never having all the answers.

What are some of your hobbies?
Hunting and fishing are still the big ones! And it seems like on weekends, I’m involved in some type of volunteer project. Lakeview is a very small rural community, so if you’re not working you’re volunteering.

Watch two radiomarked hens move through Oregon’s Warner Mountains:



The Sage Grouse Initiative is a partnership-based, science-driven effort that uses voluntary incentives to proactively conserve America’s western rangelands, wildlife, and rural way of life. This initiative is part of Working Lands For Wildlife, which is led by USDA’s Natural Resources Conservation Service.