Invasion of the Pinyon – Juniper: Part II

I had a few minutes to polish and varnish a group of new samples I had collected on my last trip down to southern Utah, so I though I would provide a few examples, for those of you who run around P-J habitat.

These three examples are from San Juan County, UT.

This little pinyon sapling, which at its base was 1″ in diameter, was 57 years old, born in the mid 1960’s.

This tiny juniper sapling turned out to be 51 years old, with a 7/8″ diameter at ground level.

This little juniper turned out to be 82 years old, born about the time Hitler was invading France.

I broke the previous record of 79 years old. I got one 24″ tall juniper that was a stunning 163 years old, born at the very beginning of the Civil War.

The average age of the new samples (n=10) is 82 years old raising the overall average to 61 years old.

All samples were collected within Utah from the Idaho border south to the Arizona border. So I can not say if this holds true for central Washington.

But next time you see the BLM proposing to chain P-J as modern expansion, clip a few saplings, count the rings and see if what they are saying is true.


  1. Jerry L Thiessen Avatar
    Jerry L Thiessen

    Amazing but not surprising. Some of the knarley juniper sentinels standing guard along rocky ridges must be thousands of years old.
    Relatively speaking, the slow encroachment of junipers downslope seems to be a recent event (150 years ?) and timed with the hoards of domestic livestock that invaded the semi-arid west. Is it possible that natural and man caused fire kept juniper at bay until livestock eliminated native grasses? Are sapling junipers, like the ones in the pictures, fire resistant? The pictures show nothing much in association but bare ground, so fire now would be impossible. Thanks.

  2. Ted Chu Avatar
    Ted Chu

    Site and competition has everything to do with this. I planted junipers in my yard in Idaho Falls Idaho and in less than 15 years they were beautiful 10-12 feet tall perfectly cone shaped trees. I did not water or fertilize them however they were well spaced and did not have competition from other trees.

    1. Jonathan Ratner Avatar

      I specifically avoided closed canopy situations. The other caveat is all the data was collected within Utah so cant say anything about other systems

  3. Michael Sauber Avatar
    Michael Sauber

    Emeritus Professor from NMSU in Las Cruces, NM, Dr William Dick-Peddie (probably not still alive) wrote the book “New Mexico Vegetation – Past, Present and Future” and talks about PJ habitat and changes. “Much of New Mexico’s vegetation is in some stage of succession as a result of human-initiated disturbances such as fire, logging, and livestock grazing.”
    It’s available in various libraries and for purchase. When he came and did a talk in Silver City NM, he did mention perhaps dense grass cover prevented seeds from germinating, but after vegetation cover was grazed to nothing, small eroded channels formed on the surface of the soil which allowed the juniper seeds to stay moist enough to germinate at a higher rate.

  4. Chris Zinda Avatar
    Chris Zinda

    Asking: did you kill the trees?

    1. Chris Zinda Avatar
      Chris Zinda

      I see you did. 10.


      It’s not like multiple published academic research hasn’t already been done. And, the result common knowledge (especially in this community).

      There is nothing new in what you did, erasing the lives of 10 individuals w/hundreds of cumulative years, almost all older than you. Again, for what? For your edification and site content?

      A broken record, it’s conservation in action, the preservation of these 10 trees chalked up to “education”.

      1. Jonathan Ratner Avatar

        Why I started this project was a concern that the agencies were underestimating actual ages of trees in their eradication efforts. I found no literature aging trees at ground level (to get closer to germination year).

        When I looked at what was out there from dendochronologists what I found is they were using the estimate of 15 years to get to 5 feet (BH) which was way off from what I was finding across Utah

  5. Nancy Stradtner Avatar
    Nancy Stradtner

    About 26 minutes in

    from 9 years ago re: sage grouse habitat.

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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