Week 7, Day 5: Forest Restoration

Firefighters work to ensure that a prescribed burn does not impact the village of Tyuonyi at Bandelier National Monument. (Photo by Sally King/NPS)

The forests of Northern New Mexico are much denser today than they were historically because of the legacy of 150 years of fire suppression in our wildlands.

Today in Take It Outside, learn about efforts to return the forest to healthier conditions. Look for a bonus blog post on our website tomorrow and then join us to learn about bugs next week!

Upcoming Events:

PEEC is hosting a few virtual events this weekend! Join us tonight at 7 PM for a Stump the Astronomers live-streamed panel. Bring your toughest questions and try to stump our team of experts! Learn more and register here.

Additionally, join us on Sunday for a virtual yoga class from PEEC’s Christa Tyson at 10 AM. Sign up for that class here.

We have a variety of other events coming up in May! Check out our public events calendar to see what we’re offering and register for these programs.

Blog Post:

Read about the efforts that are being undertaken in the Jemez Mountains to restore our forests in today’s blog post, which is based on an interview with Bob Parmenter, Chief of Science and Resource Stewardship at the Valles Caldera National Preserve.


Restoring riparian areas, as we will see in our bonus blog post tomorrow, often requires slowing down running water to allow it time to soak into the ground and to avoid eroding too much soil. Today, build a dam! Find a small running stream in a canyon bottom, and put rocks and sticks in it to make a dam.

What happens to the water? Can you slow it down? Can you make it flow in a different direction? Can you see any signs of erosion around your dam? Be sure to clear your dam when you’re finished playing.

If you can’t get to a stream, you can follow these instructions to make a stream and dam in a container at home.

Outdoor Challenge (Beginner):

Can you spot the Brown Creeper on the trunk of this ponderosa pine tree? (Photo by Craig Martin)

Look for signs of a healthy ponderosa pine forest:

  • Some large trees: too big to get your arms around the trunk
  • Patches of sunshine shining through the tree canopy
  • Grass and flowers growing on the ground
  • Signs of wildlife: birds, squirrels, deer, predators, etc.

Outdoor Challenge (Advanced):

Find out the tree density of a forest near you. Historically, ponderosa pine forests might have had a density of about 40 – 60 trees per acre. In very overgrown forests, there may be up to 2,000 trees per acre!

Go to a forested area near you. Walk off an area of about 66 x 66 ft (about 30 steps in each direction). Mark the corners of your area. This will be about a tenth of an acre. Now count the trees inside. For a historical density, there would be 4 – 6 trees in your plot. Depending on where you are, you might find more like 100 trees or more! Can you imagine how a historically-dense forest would look compared to a very dense forest? How would the sizes of the trees differ? What would happen if lightning started a fire in your plot?

Tell us what you think in the Google Form below or by emailing us at takeitoutside@peecnature.org.

Other Resources:

Share Your Experience:

Tell us about the trees and forested areas near you! We’d love to see your photos, too. Please send them to takeitoutside@peecnature.org or share them on Facebook or Instagram with the hashtag #peectakeitoutside.

Join us next week to explore bugs!

Forest Restoration in the Jemez Mountains

A firefighter manages a burning pile of dead and downed wood during a pile burn operation in Upper Pueblo Canyon in January 2015. (Photo by Craig Martin)

By Siobhan Niklasson, based on a conversation with Bob Parmenter of the Valles Caldera

The forests of the American West look much different today from how they looked 150 years ago. Around that time, a handful of large and destructive fires in the United States convinced land managers and the public that fires should be stopped as soon as possible in order to protect natural resources.

However, the decision to suppress wildfires had unintended consequences. Historically, frequent fires in ponderosa pine forest removed excess growth and kept the landscape open. Historical ponderosa pine forests were described as open and park-like and it was said that you could ride a horse through the forest for miles without hitting your head on a branch. This 2011 article from The Durango Herald gives some insight into the history of the forests of the Jemez Mountains and how fire suppression changed them

Without fire to clear the landscape, many more trees were able to take root, increasing the tree density from around 40 – 60 trees per acre to 1,000 – 2,000 trees per acre in some cases. It’s painful just to think about trying to ride a horse through such a dense forest! 

An overgrown stand of trees at Banco Bonito in the Valles Caldera before and after thinning. The before photo, on the left, was taken in 2011. The after photo, on the right, was taken in 2014. (Photos by Bob Parmenter/NPS)

So many trees in the forest meant that each tree had to compete for water and nutrients with all its neighbors, surface water running in streams was reduced, sunlight was largely blocked from the ground level, leading to a dearth of grasses and other understory plants, and animals that depended on these small plants for grazing were squeezed out. Crucially, for fires, the increase in fuel in the forest turned what would once have been healthy ground fires into raging infernos that could wipe out an entire forest, and get so hot that the soil was sterilized.

Today, we have a better understanding of the importance of fire in our forest ecosystems. But the 150 years of fire suppression policy left a legacy of overgrown forests that must be returned to a healthy state, both to restore healthy ecosystems, and to reduce the risk of severe megafires.

In the Jemez Mountains, agencies have joined forces in a collaborative forest landscape restoration program to undertake this work. The first step is to thin the forest using mechanical means or cutting by hand to reduce the density from 1,000+ trees per acre to about 100 trees per acre. This means potentially cutting out 90% of the trees in the area! Once the trees are cut, they can either be removed and used for wood products, or they can piled and burned. This work is expected to be completed in the southwestern Jemez Mountains within another two to three years.

Once the forests are thinned, natural mortality will further reduce the number of surviving trees. The idea is that after another 100 – 200 years, we will end up with a mature forest with about 40 – 60 trees per acre.

With the first thinning completed, natural and prescribed fire can be used to manage the forest. It’s much cheaper and safer to manage fire in a thinned forest than it is to bring in helicopters and air crews to battle high-intensity fires that threaten lives and neighborhoods. For example, the 2011 Las Conchas fire burned over 150,000 acres, and cost almost $50 million to control.

The 2019 Redondo Fire burned at a low intensity through forest that had been thinned, with no injuries or property damage. (Photo by Brian Faith/NPS)

In 2019, a lightning strike in the Valles Caldera started a low-intensity ground fire that burned through thinned forests. Firefighters saw an opportunity to use this fire to maintain some forested areas that needed to be burned. With the cooperation of local residents, they managed to safely allow the fire to burn right up to the boundary between the preserve and the Sulfur Flats neighborhood.

For the trees, thinning makes it easier for each individual tree to secure the resources (water and nutrients) it needs to survive. This should help the trees be more resilient to rising temperatures due to climate change.

A tree can live for several hundred years. Even if we are able to reverse the trend in our greenhouse gas emissions by 2050, we can expect temperatures to keep rising for another 50 years after that, and it could be an additional 50 years before temperatures cool off again.

So while that timescale of around 150 years is a long time in human terms, it means that the trees that are living now could potentially see the other side of the climate change curve, if we can help them survive fires and beetle infestations now.

Next time you’re out, see if you can find signs of forest thinning and prescribed burns. This is important work that’s keeping our forest ecosystems healthy for everything, including us, that depends on them.

Learn more about the history of forest fire suppression here.