The Invasion of the Pinyon Juniper

Typical Pinyon Juniper in the Skutumpah area of the Grand Staircase Escalante National Monument.

Back in 2017, the Grand Staircase Escalante National Monument, the supposed ‘crown jewel’ of the BLM’s National Landscape Conservation System proposed a massive pinyon-juniper (P-J) removal project in the Skutumpah area. The BLM announced that the project’s purpose was to remove post-European settlement ‘invading’ P-J and create sage grouse habitat.

Given my experience that virtually everything the BLM says about its ‘management’ is, at a minimum, a stretch of the truth and far more often blatant fabrication, I thought it would be good to go get some dirt time in the project area and see what was actually there.

While P-J is despised by the agencies and ranchers west-wide, Utah is the heart of this irrational hatred. The State of Utah spends hundreds of millions of tax-payer dollars eradicating PJ, not just on state lands but primarily on BLM and Forest Service lands.

According to Utah’s website, they have completed 2,707 project covering 2.5 million acres at a cost of nearly half a billion dollars, and most of this is P-J eradication.

Before heading down, I ordered a tree corer so I could age the trees and did some GIS to generate random points within the project area and developed a study protocol to core and measure the attributes of the largest tree at each of the random points and then run a transect from that tree 200’ due north and south and measure the trees along the transect in order to correlate tree circumference with the known age and circumference of the cored tree. I also collected data along the transect based on the USGS Circular 1335 Piñon and Juniper Field Guide: Asking the Right Questions to Select Appropriate Management Actions.

Even a few minutes walking through the area would have informed anyone with the slightest knowledge or professional integrity that this was old-growth P-J, it had never been sage grouse habitat in the last few hundred years and was not post-European invasion P-J expansion.

But, as usual, we did the BLM’s job for them since they lacked the interest to base their management on facts and we collected real data from dozens of the random generated points and the data was clear. Tree age ranged from about 160 to 375 years old.

249 year old pinyon.

I took the cores and photos into the Assistant Field Office Manager and he was surprised his staff didn’t mention this reality when they pushed the eradication project.

As a result, the project was put on hold and he bought a corer and told his staff to verify what we had done.

But a question lingered in my mind. How many years was the tree alive before the first ring would be detected by the corer, because this would need to be added to the core age to get to the actual age. At the time I was coring, I estimated that it would take about 15 years to go from germination to ~18” above ground level where the core was extracted.

There are two factors that would determine where along the trunk of the old tree that the core could be extracted. First is the deposition of organic matter, which under an old tree is generally at least 6” but can be as much as 12” deep.

Second is the root wad inflation where the soil surface rises over time as the root system of the tree expands. This also can be in the range of 6-12”. The closest you can core due to the handle of the corer is about 12” above the current soil surface. So when you add this together you would get a minimum of about 18 to 24” from the core location to the soil surface when the seed originally sprouted.

So to help answer this question, how old is P-J at 18-24” tall, I started collecting samples of 18-24” tall P-J saplings across the state of Utah as I was traveling around for other projects. I have a sample size of about 70 across the state and the results so far have been mind blowing. The average age of the dataset is 51 years old with a maximum of 77 and a minimum of 20.

This one below is 66 years old and about the thickness of my little finger.

A 77 year old juniper a little thicker than my thumb.

So in the Skutumpah example this would make the age range from 211 to 426 years old, a far cry from the bogus 50-100 years the BLM was claiming.

Just across the road from this project area is the boundary between the Grand Staircase Escalante National Monument and the Kanab Field Office. On the other side of the road from the Grand Staircase’s proposed cutting, the Kanab Field Office authorized the eradication of its old-growth P-J and as could have been easily predicted the old-growth forest was transformed to 5-7 species of invasives ranging from cheatgrass to a number of invasive mustards.

Here is what it looks like…

The two morals of this story are:

  1. Never believe anything the agencies say, without verification
  2. Do the on-the-ground work needed, collecting data, don’t just sit in an office and respond to paper, like most conservation organizations these days. Get out and know the ecosystems you are trying to protect, intimately

You can find out more about our work at Sage Steppe Wild.





  1. Chris Zinda Avatar
    Chris Zinda

    Back in the early 90s, we’d collect garbage (flagging) hanging from trees in this same area that was before and since after chained, today eaten by even “better” machines.

    Utah is gross.

  2. Jeff Hoffman Avatar
    Jeff Hoffman

    A lot of Mormons are ranchers, so of course they hate pinion juniper. Utah is an extreme anti-environmental state. When I was with Earth First!, we were warned not to wear our Earth First! t-shirts in that state in order to avoid getting beat up. Not at all surprised that lies like this come out of Utah.

    1. easternsierraheidi Avatar

      Pinyon/Juniper forests are also being removed in Nevada and Eastern California.

  3. easternsierraheidi Avatar

    I am astounded that the BLM manager listened, let alone acted on your core information. I brought up the concept of plant succession after being told the trees were “encroaching” near my home. The contact person on the project refused to speak to me again.

    According to the North American Breeding Bird Survey the Pinyon Jay populations fell 85% between 1966 and 2015. The decline is due to loss of habitat. The loss of habitat is due to deliberate decimation of the Pinyon/Juniper forests along with drought and an increase in devastating wildfires. In the attempt to do whatever the hell the land managers are trying to do they are also driving the Pinyon Jay to extinction. May there be yet another seat in that special place in hell.

  4. Ida Lupine Avatar
    Ida Lupine

    Terrible. What a shame. Painful.

  5. Garry Rogers Avatar

    Impossible to thank you enough for the work you are doing. Just know it is truly appreciated.

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Jonathan Ratner

Jonathan Ratner has been in the trenches of public lands conservation for nearly 25 years. He started out doing forest carnivore work for the Forest Service, BLM, and the Inter-agency Grizzly Bear Study Team, with some Wilderness Rangering on the Pinedale Ranger District. That work lead him directly to deal with the gross corruption within the federal agencies' range program.

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Jonathan Ratner