tailoring management to the inherent variability of pj ... · 10/13/2016 · tailoring management...

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




- 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




- 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


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


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


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 …)

tailoring management to the inherent variability of pj ... · 10/13/2016 · tailoring management...

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