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Tailoring management to the inherent variability of PJ vegetation
Bill Romme, Colorado State University PJ symposium, Albuquerque Oct. 13, 2016
Question: What is your management objective in a PJ stand or landscape?
Maybe the objective is restoration of a historic scene…
Inscription Rock 1891 Inscription Rock 2009
Question: What is your management objective in a PJ stand or landscape?
Maybe the objective is restoration of a historic scene…
Inscription Rock 1891 Inscription Rock 2009
- Removing the trees around the base of the rock would be a structural restoration … but maybe not a functional restoration … and might require repeated treatments to sustain the historic view
Question: What is your management objective in a PJ stand or landscape?
Maybe the objective is restoration of a historic scene…
Inscription Rock 1891 Inscription Rock 2009
- Removing the trees around the base of the rock would be a structural restoration … but maybe not a functional restoration … and might require repeated treatments to sustain the historic view - A reasonable objective in a history-oriented monument like El Morro … but maybe not in a landscape like Gila Wilderness, where emphasis is on “untrammeled” character
A functional restoration emphasizes re-establishment of historical or “natural” ecological processes … requires understanding of how those processes have changed since the reference period
Processes in savannas may have changed the most … - Removal of period burning may have allowed extensive tree establishment & expansion … return of periodic burning might be a centerpiece of functional restoration … and this might hinge on restoration of the grass component
Processes in persistent woodlands may have changed the least … - Infill may have occurred, but maybe largely climate-driven (“natural”) - Fire exclusion not such a big factor here, because low-severity fires were never frequent and did not shape vegetation structure as in savannas
More on restoration: We often have a “tree-centric” perspective on the changes that have occurred and on the components that need attention …
but often it’s the understory that needs help more than the canopy
Persistent PJ on Kaiparowitts Plateau, Utah -- beautiful multi-age canopy, inc. very old trees -- but patches of cheatgrass throughout -- cheatgrass may dominate if the area burns
More on restoration: We often have a “tree-centric” perspective on the changes that have occurred and on the components that need attention …
but often it’s the understory that needs help more than the canopy
Persistent PJ on Kaiparowitts Plateau, Utah -- beautiful multi-age canopy, inc. very old trees -- but patches of cheatgrass throughout -- cheatgrass may dominate if the area burns
After the 2002 fire on Mesa Verde
To functionally restore a PJ savanna, we may need to pay more attention to the grass than to the trees
Wupatki … ignitions throughout 20th century, but no spreading fire until grass cover was restored * A challenge for researchers & managers: devise livestock grazing systems for PJ savannas that sustain sufficient grass cover to carry periodic fires -- large ranch adjacent to Wupatki … conservation oriented & conscientious … but no fires
More on burning juniper savannas: the Wuptaki experience …
Recent fires mostly killed small junipers (head-high or smaller) … larger trees unharmed or only partially killed
Root competition (apparently) leads to a ring of bare ground around the base of a large juniper … protects the crown from igniting as grass fire sweeps by
With fire, we may be able to at least partially restore a PJ savanna, i.e., kill many of the small trees that have expanded into the grassland or filled in a previously sparse woodland But fire alone may not be sufficient to kill the larger, older trees … may need mechanical treatment … or may need acceptance of the new system Also: make sure the herbaceous community is responding well to the burning (black grama?)
With fire, we may be able to at least partially restore a PJ savanna, i.e., kill many of the small trees that have expanded into the grassland or filled in a previously sparse woodland But fire alone may not be sufficient to kill the larger, older trees … may need mechanical treatment … or may need acceptance of the new system Also: make sure the herbaceous community is responding well to the burning (black grama?)
Unexpected twist at Wupatki: large trees killed
if tumbleweeds had accumulated beneath the
crowns
Question: What is your management objective in a PJ stand or landscape?
Maybe the objective is to increase or enhance overall biodiversity … Old-growth persistent woodlands actually may not need any enhancement
: Plant & fungal diversity in old-growth woodlands in Mesa Verde National Park:
209 forb & shrub species 21 grasses 99 fungi 179 lichens 24 mosses
Question: What is your management objective in a PJ stand or landscape?
Maybe the objective is to increase or enhance overall biodiversity … Old-growth persistent woodlands actually may not need any enhancement
: Plant & fungal diversity in old-growth woodlands in Mesa Verde National Park:
209 forb & shrub species 21 grasses 99 fungi 179 lichens 24 mosses
But particular species may need help … maybe focus active treatments on areas of recent expansion, not old-growth
Question: What is your management objective in a PJ stand or landscape?
Feasible? … yes Effective? … maybe yes, maybe only somewhat so … old persistent woodlands may be most challenging Example from Mesa Verde
Maybe the objective is to mitigate fire risk/hazard by reducing fuels…
Most effective mechanical fuel reduction treatment includes some level of thinning plus removal of lower branches
* Note that this is NOT ecological restoration … this is NOT pre-1900 stand structure in Mesa Verde
What to do with the material
generated by mechanical thinning?
Although Piñon wood is suitable for a variety of
products, processing and hauling costs are often
too high for this material to be utilized.
Currently a high percentage of Piñon is left
masticated on site.
Need for R&D to utilize Piñon wood for value-
added products
Kurt Mackes, Center for Utilization of Small-
Diameter Wood, CSU …
Traditional Uses for Piñon
Christmas trees
Firewood
Novelties
Mine timbers
Railroad ties
Pulp
Charcoal
Piñon nuts
Courtesy of Kurt Mackes, CSU
Time to monitor our treatments …
Purposes of monitoring: -- See if we accomplished what we intended -- See if we caused any unexpected, undesirable outcomes
* Learn from our mistakes so that we don’t make them again
Time to monitor our treatments …
Purposes of monitoring: -- See if we accomplished what we intended -- See if we caused any unexpected, undesirable outcomes
* Learn from our mistakes so that we don’t make them again
The best kind of monitoring is a rigorous scientific study … e.g., Lou Bender yesterday … but how many of us have time or money for that kind of work?
* Nevertheless, we all can do a simplified form of monitoring (science actually) that won’t lead to a scientific publication, but will help us to avoid making mistakes next time …
* A recommendation from Dan Binkley, CSU *
20
A new way for YOU (!) to think about Science:
-- from Dan Binkley
“Pocket science”
The Best Available Science comes in all sizes and budgets
Million $ Research Science
100 Billion $ Defense science
Billion $ Rocket science
-- from Dan Binkley
“Pocket Science” may provide a link between general knowledge and case-specific needs and details A key focus of pocket
science is learning by doing
“Pocket science won’t get you to the moon, but it can keep you from making the same old mistakes.”
-- from Dan Binkley
Principles of Pocket Science:
1. Never treat an entire unit the same; always leave a portion untreated, and always treat another portion differently.
2. Always GPS and photograph
3. Commit 2 days each year to revisiting Pocket Science projects: Always aim to find out when you’ve been wrong!
-- from Dan Binkley
Thinning and mastication of slash in a Colorado juniper woodland to create a fuel break along the boundary between federal & private land
- Will ground layer vegetation be suppressed? - Will the slash burn more intensely than the forest? - Will weeds invade the site?
Thinning and mastication of slash in a Colorado juniper woodland to create a fuel break along the boundary between federal & private land
- Will ground layer vegetation be suppressed? - Will the slash burn more intensely than the forest? - Will weeds invade the site?
“Pocket science” can answer these questions … and will improve the next treatment
“Pocket Science” may provide a link between general knowledge and case-specific needs and details A key focus of pocket
science is learning by doing
“Pocket science won’t get you to the moon, but it can keep you from making the same old mistakes.”
-- from Dan Binkley
Standing back and taking a long look at your ecosystem … The more we understand about its ecological history, ecological processes & natural dynamics, the better we can do in sustaining it … many of the important processes and changes are occurring over very long time spans … we have experienced only a tiny fraction of the big picture E.g. Wupatki … juniper was rare or absent in region until ca. 500 A.D … largely wiped out by Sunset Crater eruption(s) ca. 1100 AD and by Sinagua culture soon after… gradually expanded after ca. 1300 AD Expansion was a natural ecological process … but got a big boost by the onset of industrial livestock grazing & fire exclusion in late 1800s-late 1900s Now it’s being slowed or even reversed by return of grassland fires and by climate change Where is it headed? What will be the key ecological processes & dynamics in the 21st century?
Standing back and taking a long look at your ecosystem … The more we understand about its ecological history, ecological processes & natural dynamics, the better we can do in sustaining it … many of the important processes and changes are occurring over very long time spans … we have experienced only a tiny fraction of the big picture E.g. Wupatki … juniper was rare or absent in region until ca. 500 A.D … largely wiped out by Sunset Crater eruption(s) ca. 1100 AD and by Sinagua culture soon after… gradually expanded after ca. 1300 AD Expansion was a natural ecological process … but got a big boost by the onset of industrial livestock grazing & fire exclusion in late 1800s-late 1900s Now it’s being slowed or even reversed by return of grassland fires and by climate change Where is it headed? What will be the key ecological processes & dynamics in the 21st century? (need for Lou Bender type science, and for pocket science …)