http://www.insidedenver.com/drmn/opi...581500,00.html

Speakout: Clear-cutting for runoff 'delusional'
By Harv Teitelbaum, Special to the News
December 2, 2002

The notion of clear-cutting huge tracks of forest to increase runoff for water
containments is not only self-serving industry pandering, but delusional.

While supporters hold up one carefully chosen test where some limited success
was realized, the practical, real world effects would be quite different.

Rather than being net depleters of moisture, trees and forests help increase
moisture by "fixing" it in ground and surface sources. Trees use some of the
moisture from snow in their upper stories while, aided by gravity, sun and
wind, they permit most to find its way to the surface. This surface moisture is
then shaded from excessive evaporation by the trees, allowing it to percolate
downward, maintaining soil moisture balance, feeding root systems, reducing
erosion, and recharging ground sources. Evapotranspiration from trees helps
maintain the water cycle and local climate.

On the other hand, open landscapes of snow are like open water reservoirs,
i.e., massive moisture evaporators. Not only would the result of massive
clear-cutting be a net loss of ground and surface moisture due to increased
evaporation, but the unshaded soil would lose moisture in the summer and
whenever it lacked snow cover in winter, it would dry and harden thus favoring
weeds and other invasives over native grasses and forbs, and erosion would
increase.

Plant and animal diversity would decrease. Population imbalances would
increase.

A Canadian study found that south-facing slopes received, on average, five
times the solar radiation as north-facing slopes and, as a result, produced
much less runoff compared to north-facing slopes. In many areas, the study
found that south-facing slopes produced no consequential runoff at all. Not
surprisingly, south-facing slopes also have a much higher fire frequency. So
the irony is that clear-cutting south-facing slopes for fire mitigation might
also eliminate what little runoff potential there is, as tree cover is the only
feature allowing these aspects to retain moisture. At the same time,
clearcutting north-facing slopes might benefit runoff in limited applications,
but have far less potential to mitigate fire frequency.

The Lake District of northern England is indicative of what can happen to a
landscape after its forests have been removed. Until recent restoration efforts
began, centuries of clear-cutting had left this area almost completely devoid
of trees. The result is a stark region of little more than sheep grass and
rocks. The soil has become so paper thin that there is little left to erode.
Travelers are continually making new trails, as even a few passes expose the
loose rocky substrate. Wildlife is almost nonexistent; the climate, unmoderated
and severe.

Imagine what would happen if Colorado took this scheme to its logical extreme.
We know that most of our water supply comes from snowpack and not rain.
Significantly reducing forest cover, combined with global warming, itself
exacerbated and ignored by the same industry-government alliance, would further
skew our precipitation mix toward rain. The long-term effect would not be
increased water supply for developers, but the desertification of the eastern
half of our state.

Less snow, less overall precipitation, less ground source recharge, altered and
desertified ecosystems - these are just some of the consequences of this
scheme. There will almost certainly be others. Of course, if recent official
attitudes are any indication, even desertification and the drying up of much of
our water supply would not hold developers back. This is an indication of where
both the real problem and real solution lie.

Clear-cutting and other supply-side schemes of developers and conservatives
could be compared to buying new and shinier buckets rather than fixing the hole
in the roof. Proposals for new containments, whether or not they prove
temporarily effective, merely distract us from considering the kinds of growth
controls necessary to get a real handle on our water supply problems.

Only after controlling demand will efforts at securing an adequate supply have
any hope of success.

Meanwhile, instead of clear-cutting, the logical course might be to uniformly
thin smaller-bore trees across all slopes, while removing brush and litter.

This would decrease fire severity and modestly increase runoff opportunity,
while maintaining the hydrological cycle, ground source recharge, shade,
biodiversity and habitat. Doing so at lower elevations would aid fire
mitigation, while thinning at higher elevations might improve runoff.

In article ,
writes:

The notion of clear-cutting huge tracks of forest to increase runoff for water
containments is not only self-serving industry pandering, but delusional.

While supporters hold up one carefully chosen test where some limited success
was realized, the practical, real world effects would be quite different.

Rather than being net depleters of moisture, trees and forests help increase
moisture by "fixing" it in ground and surface sources. Trees use some of the
moisture from snow in their upper stories while, aided by gravity, sun and
wind, they permit most to find its way to the surface. This surface moisture is
then shaded from excessive evaporation by the trees, allowing it to percolate
downward, maintaining soil moisture balance, feeding root systems, reducing
erosion, and recharging ground sources. Evapotranspiration from trees helps
maintain the water cycle and local climate.

Do you have any actual research to back this position? Generally I am of
the opinion that any ground that can grow trees should be growing trees,
but in some areas of the world trees are discouraged because of the
amount of water they use. I have talked to a farmer in South Africa who
was not allowed to plant trees in a riparian zone because of the amount
of water they would consume.

It takes about 20" of rain a year to grow a douglas fir. I'm sure the
Rocky Mountain pines are more frugal with their water, but just about
have to consume around a foot of rainfall a year.

What the result of logging would be on water supply is not clear to me.
I suspect it would be highly variable depending on slope and climate.

Probably the most effective way for Colorado to recover water is just to
outlaw lawn irrigation.

--
http://home.teleport.com/~larryc

In article ,
writes:

The notion of clear-cutting huge tracks of forest to increase runoff for
water
containments is not only self-serving industry pandering, but delusional.

While supporters hold up one carefully chosen test where some limited
success
was realized, the practical, real world effects would be quite different.

Rather than being net depleters of moisture, trees and forests help
increase
moisture by "fixing" it in ground and surface sources. Trees use some of
the
moisture from snow in their upper stories while, aided by gravity, sun and
wind, they permit most to find its way to the surface. This surface
moisture is
then shaded from excessive evaporation by the trees, allowing it to
percolate
downward, maintaining soil moisture balance, feeding root systems, reducing
erosion, and recharging ground sources. Evapotranspiration from trees helps
maintain the water cycle and local climate.

Do you have any actual research to back this position?

What?? = Evapotranspiration maintaining the water cycle and local Climate


Generally I am of
the opinion that any ground that can grow trees should be growing trees,
but in some areas of the world trees are discouraged because of the
amount of water they use.

The article was in response to the Option of Clear-cutting tress to increase
run off for storage behind Dams!

I have talked to a farmer in South Africa who
was not allowed to plant trees in a riparian zone because of the amount
of water they would consume.

The one I saw was they were removing non-natives in Sought Africa which sucked
up water and crowded out Natives!

Surprise = Surprise:

Colorado has just banned The sale of Russian Olive Trees!



It takes about 20" of rain a year to grow a douglas fir. I'm sure the
Rocky Mountain pines are more frugal with their water, but just about
have to consume around a foot of rainfall a year.

Their concern was that the snow would not fall on to the ground and would melt
in the trees and evaporate!



What the result of logging would be on water supply is not clear to me.
I suspect it would be highly variable depending on slope and climate.

They want increased run off!



Probably the most effective way for Colorado to recover water is just to
outlaw lawn irrigation.

Well in Denver, the rat catchers are called out everytime someone plants Native
Grass which gets too high = Menawhile in the House next dorr the wood and trash
pile is ignored - That would be where the rats would be!

Saw Denver Parks trucks out watering ground with no tress but which had flowers
during the summer - this was last week and not needed - They watered heavy =
Not a good example!



--
http://home.teleport.com/~larryc

In article ,
writes:

I have talked to a farmer in South Africa who
was not allowed to plant trees in a riparian zone because of the amount
of water they would consume.

The one I saw was they were removing non-natives in Sought Africa which sucked
up water and crowded out Natives!

In eastern Oregon, juniper is well known as a water thief. It's a major
effort, but watershed improvement projects often involve Juniper
eradication. It's expensive, because the trees are small, the wood is
inferior and there is no market for it. It is possible to substantially
enhance stream flows, but it involves killing off thousands of acres of
juniper.

Willow is another heavy water user. When pioneers encountered a seep or
bog, it was common to plant a willow in it to dry it up.

--
http://home.teleport.com/~larryc

The "water thief" concept is a bizarre one for me. I understand removing
invasive non-native species that can dominate riparian zones - tamarisk for
example - but just whose water is being stolen? Cattle? Irrigators? And
who had it before cattle and irrigators? Buffalo and jackrabbits? What is
the water balance between what used to be available to streams and basins
(i.e. fish) before settlement and now. Is juniper invasive in sage? It
would seem they'd have very different water requirements.

I recall that BC watershed study. It's been used to promote logging in city
watersheds around here. It requires very skilled forestry and limited entry
to work right.



"Larry Caldwell" wrote in message
...
In article ,
writes:

I have talked to a farmer in South Africa who
was not allowed to plant trees in a riparian zone because of the amount
of water they would consume.

The one I saw was they were removing non-natives in Sought Africa which
sucked
up water and crowded out Natives!

In eastern Oregon, juniper is well known as a water thief. It's a major
effort, but watershed improvement projects often involve Juniper
eradication. It's expensive, because the trees are small, the wood is
inferior and there is no market for it. It is possible to substantially
enhance stream flows, but it involves killing off thousands of acres of
juniper.

Willow is another heavy water user. When pioneers encountered a seep or
bog, it was common to plant a willow in it to dry it up.

--
http://home.teleport.com/~larryc

The "water thief" concept is a bizarre one for me. I understand removing
invasive non-native species that can dominate riparian zones - tamarisk for
example - but just whose water is being stolen? Cattle? Irrigators? And
who had it before cattle and irrigators? Buffalo and jackrabbits? What is
the water balance between what used to be available to streams and basins
(i.e. fish) before settlement and now. Is juniper invasive in sage? It
would seem they'd have very different water requirements.

I recall that BC watershed study. It's been used to promote logging in city
watersheds around here. It requires very skilled forestry and limited entry
to work right.

Years Ago, the Politcos in Colorado wanted to clear-cut most of the Aspen trees
becuase they felt that the trees used too much water!





"Larry Caldwell" wrote in message
t...
In article ,
writes:

I have talked to a farmer in South Africa who
was not allowed to plant trees in a riparian zone because of the amount
of water they would consume.

The one I saw was they were removing non-natives in Sought Africa which
sucked
up water and crowded out Natives!

In eastern Oregon, juniper is well known as a water thief. It's a major
effort, but watershed improvement projects often involve Juniper
eradication. It's expensive, because the trees are small, the wood is
inferior and there is no market for it. It is possible to substantially
enhance stream flows, but it involves killing off thousands of acres of
juniper.

Willow is another heavy water user. When pioneers encountered a seep or
bog, it was common to plant a willow in it to dry it up.

--
http://home.teleport.com/~larryc

Larry Caldwell writes:

In article ,
writes:

The notion of clear-cutting huge tracks of forest to increase runoff for water
containments is not only self-serving industry pandering, but delusional.

snip

Do you have any actual research to back this position? Generally I am of
the opinion that any ground that can grow trees should be growing trees,
but in some areas of the world trees are discouraged because of the
amount of water they use. I have talked to a farmer in South Africa who
was not allowed to plant trees in a riparian zone because of the amount
of water they would consume.

I think the idea behind this scheme only would apply to east slope areas
that are prone to chinook winds. I recall several studies in Alberta
that showed a net moisture gain from an east-slope area that had a
patchwork of small clearcuts. I don't have any references handy, but
might be able to find them if anyone is interested.

The mechanism was that all the winter snow in the small clearcuts reached
the ground and was protected from evaporation by the surrounding trees,
while the undisturbed area lost about 1/3 of the snow moisture to
evaporation over the winter, as almost all the snow held in the crown
branches evaporated. This effect was lost in openings over about 20 ha
in size, because the sheltering effect of surrounding bush was lost in
larger openings.

I have no idea what effect on the downwind water cycle this might have
if undertaken on a large scale.

--
Larry Stamm

http://www.larrystamm.com

In article ,
writes:

The "water thief" concept is a bizarre one for me. I understand removing
invasive non-native species that can dominate riparian zones - tamarisk for
example - but just whose water is being stolen? Cattle? Irrigators? And
who had it before cattle and irrigators? Buffalo and jackrabbits? What is
the water balance between what used to be available to streams and basins
(i.e. fish) before settlement and now. Is juniper invasive in sage? It
would seem they'd have very different water requirements.

It's all management, Mike. Fish and sage grouse are having a hard time,
while there is no shortage of juniper or the species that eat juniper
berries. In areas that get less than 15" of rainfall a year, juniper
will exterminate all competing vegetation, including sage.

It's interesting that you mention buffalo, because buffalo kill trees.
The Great Plains are a fossil artifact of the great buffalo herds that
used to kill off all the trees. Now that the buffalo are gone, trees are
encroaching on areas that are not farmed or disturbed. It takes a while
for a seed reservoir to build up, but 500 years from now the Great Plains
will be the Great Central Forest.

--
http://home.teleport.com/~larryc

"Larry Caldwell" wrote in message
...
In article ,
writes:

The "water thief" concept is a bizarre one for me. I understand
removing
invasive non-native species that can dominate riparian zones - tamarisk
for
example - but just whose water is being stolen? Cattle? Irrigators?
And
who had it before cattle and irrigators? Buffalo and jackrabbits? What
is
the water balance between what used to be available to streams and
basins
(i.e. fish) before settlement and now. Is juniper invasive in sage?
It
would seem they'd have very different water requirements.

It's all management, Mike. Fish and sage grouse are having a hard time,
while there is no shortage of juniper or the species that eat juniper
berries. In areas that get less than 15" of rainfall a year, juniper
will exterminate all competing vegetation, including sage.

It's interesting that you mention buffalo, because buffalo kill trees.
The Great Plains are a fossil artifact of the great buffalo herds that
used to kill off all the trees. Now that the buffalo are gone, trees are
encroaching on areas that are not farmed or disturbed. It takes a while
for a seed reservoir to build up, but 500 years from now the Great Plains
will be the Great Central Forest.


The old explanation for the Great American Desert that I recall was wind -
too much evapotranspiration to allow broadleaved trees except in valleys and
on streams but ideal for grass. I wouldn't discount long term effects of
fire, plowing or grazing either. Restoration experts have managed to bring
back small parcels of pre-settlement plant communities just by fencing OUT
the cattle. Pioneer graveyards usually held reservoirs of original plants
that stopped abruptly at the fenceline.
If juniper is advancing is it because of less grazing, less fire, less
management or a change in climate? Succession should follow the usual
rules.

In article ,
writes:

The old explanation for the Great American Desert that I recall was wind -
too much evapotranspiration to allow broadleaved trees except in valleys and
on streams but ideal for grass. I wouldn't discount long term effects of
fire, plowing or grazing either. Restoration experts have managed to bring
back small parcels of pre-settlement plant communities just by fencing OUT
the cattle. Pioneer graveyards usually held reservoirs of original plants
that stopped abruptly at the fenceline.

I'm sorry I jumped from discussing desert and sage brush to the great
plains. It confused the issue. The part about the advance of forests
into the plains had nothing to do with desert areas. Cattle are nowhere
near as destructive of trees as bison. I think fire suppression has a
lot to do with it too, since burning is a great way to maintain
grasslands.

I don't know what area they are talking about clearing in Colorado, but
there is a good chance that some of it was not historically forested.
Mountain bison were a separate, somewhat smaller strain than the plains
bison that inhabited the mountain states.

If juniper is advancing is it because of less grazing, less fire, less
management or a change in climate? Succession should follow the usual
rules.

I think less fire is the biggest reason. Juniper has a very oily wood
that burns like a candle. There is an article that gives some mention of
juniper clearing at

http://www.nv.blm.gov/bmountain/fore...front_page.htm

It's a Nevada BLM site, but the difference between Nevada desert and
Oregon desert is just a line on a map. The juniper discussion is about
halfway down the page.

--
http://home.teleport.com/~larryc

Larry Caldwell wrote in message t...
In article ,
writes:

The "water thief" concept is a bizarre one for me. I understand removing
invasive non-native species that can dominate riparian zones - tamarisk for
example - but just whose water is being stolen? Cattle? Irrigators? And
who had it before cattle and irrigators? Buffalo and jackrabbits? What is
the water balance between what used to be available to streams and basins
(i.e. fish) before settlement and now. Is juniper invasive in sage? It
would seem they'd have very different water requirements.

It's all management, Mike. Fish and sage grouse are having a hard time,
while there is no shortage of juniper or the species that eat juniper
berries. In areas that get less than 15" of rainfall a year, juniper
will exterminate all competing vegetation, including sage.

It's interesting that you mention buffalo, because buffalo kill trees.
The Great Plains are a fossil artifact of the great buffalo herds that
used to kill off all the trees. Now that the buffalo are gone, trees are
encroaching on areas that are not farmed or disturbed. It takes a while
for a seed reservoir to build up, but 500 years from now the Great Plains
will be the Great Central Forest.

It also has to deal with percipitation = seeing That The historical
range of the bison was extensive, from Alaska, Washington, Oregon, and
Canada south into the northern portions of the Mexican plateau, and
eastward to the Atlantic seaboard states, and all land in-between.
Before Europeans arrived, small herds of woodland bison inhabited
almost all of Georgia, except the southwestern and coastal parts of
the state and By 1819 all bison east of the Mississippi River were
gone forever = I think we can say more factors than just Bison or no
Bison effect the presence of trees on the great plains or in the
deserts of the Sahara!

In article ,
writes:

I think we can say more factors than just Bison or no
Bison effect the presence of trees on the great plains or in the
deserts of the Sahara!

Once again, for the geographically challenged, the Great Plains of North
America are not a desert. In fact, they are quite well watered. While
the plains get steadily dryer as you move west, the east slope of the
Rockies still gets 18 to 25 inches a year, with more rain falling in the
south.

--
http://home.teleport.com/~larryc

In article ,
writes:

I think we can say more factors than just Bison or no
Bison effect the presence of trees on the great plains or in the
deserts of the Sahara!

Once again, for the geographically challenged, the Great Plains of North
America are not a desert. In fact, they are quite well watered.

Not enough to grow a lot of crops in Colorado without water!


While
the plains get steadily dryer as you move west, the east slope of the
Rockies still gets 18 to 25 inches a year, with more rain falling in the
south.


Is that why it is called the Great American Desert?

Is that why it is called the Great American Desert?
That was the old term the pioneers used for everything between the
Cascades and the treeline halfway across Missourra. Pre Bureau of
Reclamation, it was effectively a desert unless you found some bottomland.

Is that why it is called the Great American Desert?
That was the old term the pioneers used for everything between the
Cascades and the treeline halfway across Missourra. Pre Bureau of
Reclamation, it was effectively a desert unless you found some bottomland.


A tree line also maintained by fire!