Climate Breakdown – Losing Aspen Forests in the West

The Aspen Decline

What will our forests in the west be like in fall without those golden yellow leaves shining in the sun?  Aspen forests in the Intermountain West support levels of biodiversity only exceeded by riparian (stream) communities.  In this time of Climate Breakdown, aspen have been declining due to drought and temperature stress, with die-offs of large areas in the Western US in recent decades.   Water stress during drought creates air bubbles in the water  transport system of aspen, blocking flow of water and leading to mortality.  Forest dieback during drought was simulated under a high emissions climate scenario showing that drought stress will exceed the mortality threshold for aspen in the Southwestern US by the 2050s.

Climate Breakdown

We hear slogans such as “net zero by 2050”, meaning we  store  as  much carbon as we release.  But the facts reveal that this  goal will not be met.  The world growth  in energy demand, meat production, and population almost certainly will cause exceedance of the mortality threshold for aspen.  Triage in the form of major changes  in western land management is a must if we  are to have a chance to save aspen, other western plant communities, and the wildlife that depend upon them. 

Technologies such as Artificial Intelligence  and crypto currency with their large data centers consume huge amounts  of energy.   AI consumes 33 times more energy than traditional computing systems.  Barclay’s estimated that the global demand for oil would increase by 15% by 2050 despite adoption of  electric vehicles and potential efficiency gains, air travel would place greater demand on oil, and petrochemicals will be the biggest contributor to oil consumption as demand continues to grow.  In their “Deadlock” scenario, Barclay’s predicted that the  world will fall way short  of the goals of the Paris Agreement.  This is due to the inability to decarbonize and lack  of political will.   Livestock production emissions are currently estimated at 11.1 –  19.6 percent of global emissions while global consumption of meat is expected  to increase by 90% by 2050.

The U.S. Energy Information Administration acknowledges this. “Our projections indicate that resources, demand, and technology costs will drive the shift from fossil to non-fossil energy sources, but current policies are not enough to decrease global energy-sector emissions. This outcome is largely due to population growth, regional economic shifts toward more manufacturing, and increased energy consumption as living standards improve.”  The UN Environment Programme also:  “The world is in the midst of a triple planetary crisis of climate change, biodiversity loss and pollution and waste. The global economy is consuming ever more natural resources, while the world is not on track to meet the Sustainable Development Goals.”  

Livestock Exacerbate Aspen Decline in the Western US

This  is a dire situation exacerbated by the grazing of livestock on hundreds of millions of acres of our public and private lands in the Western US.  Approximately 70 percent of National Forest and 90 percent of Bureau of Land  Management managed lands are leased for livestock grazing.  Other  public lands managed by the Fish and Wildlife Service, National Park  Service, States, and localities also permit livestock grazing. 

A review of livestock grazing effects shows that livestock trample and compact the soil, leading to accelerated runoff and decreased infiltration of water into the soil.  They remove the ground covering vegetation that shades the soil, thus increasing soil temperatures and evaporation.  These factors combine to reduce soil water and elevate the water stress in plants already stressed by drought.  Agencies and landowners must manage livestock to protect aspen stands so they and the wildlife that depend upon them have a chance to persist.   Here, we use National Forests in southern Idaho and Utah as examples of failure in this respect but this failure is west-wide when it comes to addressing this major stressor of our ecosystems.

The Ashley National Forest Plan to Save  Aspen

The Ashley National Forest is a diverse area with high peaks, forests, meadows, lakes and streams.  It includes part of the High Uintas Wilderness. It contains habitat for a variety of birds and animals including Canada lynx, black bears, northern goshawk, Rocky Mountain bighorn sheep, deer, elk, moose, native  cutthroat trout and others.

In an October 2023 Decision the Ashley NF approved the Ashley National Forest Aspen Restoration Project.   This project was planned to “treat” up to 177,706 acres that  would include any aspen community in the Forest.  The treatments included prescribed burning, logging, mastication, chainsaws, girdling conifers, and ripping aspen roots with heavy equipment.  These destructive measures were intended to stimulate regeneration  of aspen stands.  Eighty-three percent of the project  would be carried out in roadless areas.  The Forest Service uses an Orwellian twist on language to describe destructive activities such as logging and burning as “restoration” as if these forests didn’t do just  fine before we came along with our livestock and destructive machines.

The Environmental Assessment produced by the Ashley NF noted, “Many aspen populations across the west are declining due to drought, browsing by large animals such as cattle, elk and deer, and lack of disturbance, particularly fire, requiring active restoration efforts to maintain and improve aspen forest health in the region.”  We mapped the fire history and use of prescribed fires in the past in the project area.  

Significant areas had already been subjected to fires,  so why the decline in aspen?  There was no analysis of this fact by the Forest Service as they proposed more burning, and to date, Ashley NF has not addressed the major issue, that of livestock grazing.

We provided in-depth comments and an objection to this project using best available science asking that the effects of livestock grazing, stocking rates, and suitability of grazing these areas be addressed.  Their response to detailed public input such as this was to deflect.  In this case, the Decision Notice stated, “Other comments such as range capabilities are not described in detail in this decision due to the fact that many of the concerns were outside of the scope of this project.”

So, a major stressor, livestock grazing, is outside the scope of the project.  This is typical of responses we receive from the Forest Service when we ask that well established principles of range science be applied so livestock grazing is managed within the capacity of the land and is balanced with the needs of wildlife, plant communities, and watersheds as the governing  laws and regulations require.  

The problem for the Forest Service is that  if these principles were  applied, stocking rates and numbers  of livestock would be greatly reduced.  This is not politically tolerable, so it is better  to deflect and deny or not address the issue at all.  Our team filed litigation against the Forest Service to stop this Aspen Restoration Project, resulting in it being withdrawn.     

Water Developments –  Industrialization of the Forest for Livestock

Because water developments (troughs, ponds, pipelines) are used by the Forest Service and other land managers to increase the extent of livestock access into previously little used areas, we requested their data for the locations of these water developments in the Ashley NF. 

It turns out there are  1,755 of these water developments.  When we  mapped them and their proximity to aspen stands, there were few aspen stands that were more  than a quarter mile from at  least one water development, thus ensuring that livestock would have easy access to most stands.  Despite this massive number, the Ashley NF  had previously approved adding more of these developments which can result in adverse effects up to a mile or more away.   Adding these developments is a typical response when degradation by livestock is noted,  a placebo to keep the status quo in numbers of cattle and sheep.  This  is common across the West.

Is the Forest Service Engaged in Willful Blindness?

In 2000, we surveyed habitats in the Bear River Range in SE Idaho’s  Caribou National Forest.  The Bear River  Range is part of the Regionally Significant Wildlife Corridor connecting the Greater Yellowstone Area to the Uinta Mountains and southern Rockies.  In our Report, we showed how livestock grazing had degraded conditions in all habitats with the majority of 310 habitat locations including 71 aspen sites,  not functioning properly (low production, lack of recruitment, barren understory). 

This is no surprise as nearly 30 years ago the Forest Service Regional Assessments pointed out that aspen regeneration had not been successful due to heavy grazing by domesticated ungulates (meaning cows and sheep). 

In the years since those assessments and our report, we have seen no action  to reduce  or better manage livestock grazing  so plant and soil communities, stream systems, or aspen forests can recover and  sustain themselves.

 Early work by Forest  Service research scientists and others documented the loss of aspen recruitment due to livestock grazing.  A study of over one hundred aspen stands in Nevada found that in all cases where  aspen was protected from livestock, it successfully regenerated without fire or disturbance and maintained multi-aged stands. In areas exposed to livestock grazing, aspen continued to decline.

The Pando Clone of aspen  in Utah’s Fishlake National Forest is known as one of the oldest living organisms.  It is suffering from lack of regeneration and disease like so many aspen stands across the west where livestock graze.  In a 2019 Report, our team demonstrated that livestock (cattle) were removing most of the understory vegetation (70 – 90 percent).  Yet, according to the Fishlake  NF, “it is thought that the lack of regeneration is due to over browsing from deer and other ungulates. Insects, such as bark beetles, and disease such as root rot and cankers, are attacking the overstory trees, weakening and killing them. ”  There is no mention  of livestock as deer  and other “ungulates” are blamed and no acknowledgement that insects  and disease may be related to the stress from browsing and trampling by the dominant “ungulate”, cows.  They predict the Pando could be lost, yet cattle still graze while they deflect.

Agency Foot Dragging Perpetuates the Problem

In an ongoing case, the Ashley, Uinta and Wasatch Cache National Forests in Utah have been foot dragging in addressing the grazing  of tens of thousands of domestic sheep on 160,000 acres of the High Uintas Wilderness.  Once again, we have engaged  in detailed analysis, comments  and meetings, only to have any action delayed for 10 years while  the degradation continues. 

For decades I have been documenting  degradation of these alpine and subalpine areas by domestic sheep.  As the Forest Service continues delay, a team  of volunteers gathered forage  production data and we  published a paper showing that if the sensitive nature of the landscape (steep slopes, highly erodible soils) and current forage production was incorporated into a new stocking rate analysis, the numbers of domestic sheep would need to be reduced by 90 percent or more.  In other words,  this wilderness is not ecologically appropriate for livestock grazing and to do so is to intentionally destroy the ecological integrity of this precious place so that a handful of livestock  permittees can graze it with their sheep.  

Kiesha’s  Preserve – An Example of What Can Be

At Kiesha’s Preserve in Idaho, deer, elk, moose, and sage grouse  are  there year around.  When we purchased the land, aspen stands  were diseased, had insect boreholes and were dying.  We closed the Preserve to livestock 30 years ago and since then, the grasses and flowers and aspen have bounced back, the old aspen stands have died and new, healthy stands have grown back with  no insect or disease issues.  You can find no evidence of adverse effects  from deer  or elk because there is natural forage to support them. 

Deer and elk winter in large numbers on the Preserve, finding grass and shrubs  beneath  the  snow as  the plant communities have recovered from a century of livestock  grazing.  On adjacent public lands there is little residual forage left after the livestock leave the allotments, so when  an elk or deer digs through the snow, they find no forage for the energy expended. 

The Message

As  climate heating adds stress to the landscape, increasing mortality to aspen and other forest types, livestock effectively increase the effects of drought.  It is time for the Forest Service and other land managers to stop deflecting around the destruction of aspen and  native plant communities by livestock and begin to address the problem by removing water developments, reducing stocking  rates and providing long term rest so plant communities such as aspen have a chance  to recover and are  better able  to withstand drought.

For a library of books and articles on livestock grazing in the West, see Sage Steppe Wild.

Kiesha’s Preserve Photo Gallery