[obol] (Off topic somewhat) Habitat notes

[Lars and Gail Norgren]

     As a teenager my number one concern at
a local and personal level was the loss of
native plant communities, specifically prairie
and savannah in the Willamette Valley. More than
anything else I resented Douglas-fir. I never
dreamed that fairly soon there would be a host
of like-minded people. After several decades
away from Finley NWR I stopped by one September
evening after dropping our oldest son off in
Eugene. It was too good to be true. There was
scorched earth as far as I could see. My fondest
and seemingly impossible dream had been realized.
      On the other hand the shores of Fern Ridge
Resevoir were familiar to me by boat in the seventies
and still had strong savannah qualities. Today they
are choked and gloomy, almost strangled to death
by the passive approach of our state tree. Everytime
I turn around I see cheerful volunteers busy paving
the road to hell by planting Douglas-fir, secure in
the belief that they are saving the world and promoting
nature.
      I leave it to someone else to come up with a
solid philosophical argument why we should put one
anthropogenic landscape above another. There is nothing
natural about our "native" prairies. I assisted on a
bird survey on Mt Richmond , outside of Gaston(Washington
County) last June. THe land owner noted that all of the existing
oaks started growing in 1838 or earlier. He was a bit
mystified. It so happens that 90% of the Kalapuyans died
in the winter of 1833-34. No coincidence here. That's how
quickly some of our favorite landscapes start to go
without constant human intervention.
      The possibilty that Armenian Blackberry could be
a climax species has a native parrallel. There are pure
stands of Salmonberry(Rubus spectablis) in Oregon that
are 300 years old. Under such conditions the soil
does go through some weird changes.
Lars Norgren

On Feb 5, 2007, at 5:50 PM, Bruce Newhouse wrote:

>  Greg posted some thoughtful comments about habitat, to which I would  
> like to add.
>
>  "Might I heretically suggest that blackberries taking over former 
>  grasslands or other habitats is less a problem with the blackberries 
>  than it is a result of strict fire suppression."
>
>  If I understand the intent of that comment correctly, I agree.  It  
> isn't the blackberry's fault.
>
> "Grasslands in the Willamette Valley are almost totally artificial 
>  (farming and grazing).  Left alone, even without blackberries, the 
>  grasses will give way to roses, hawthorns, scotch broom, and other 
>  brushy plants within a dozen years."
>
>  I second that comment.  I spend a lot of time walking in them doing  
> wetland delineations, botanical inventories, and bird and butterfly  
> inventories, and native woody encroachment is a very serious problem.   
> (The paragraph above contains some native and some exotic invasive  
> species.)  Native tree encroachment also is a huge problem:  
> Douglas-fir in uplands and Oregon ash in wetlands, for example.   
> Encroachment by all these tree and shrub species converts the  
> grassland habitats so critical for our grassland species in decline,  
> to (using uplands as an example) coniferous forest habitat that is  
> very, very common and widespread.
>
> "If low-heat fires come through every few years then an oak stand may
>  become established over these brushy plants."
>
> Maybe.  There are a lot of other variables at play with vegetation,  
> soil and soil moisture, fuel buildup, proximity of seed source, slope  
> and aspect, etc.  For a look at what the Willamette Valley looked like  
> after several thousand years of indigenous people's management before  
> EuroAmerican settlement, check out the 1850 "presettlement vegetation"  
> map on the PNW Ecosystem Research Consortium web site at OSU. There  
> was a lot of upland prairie out there, and lots of savanna, and only  
> tiny traces are left.  (If you aren't familiar with definitions of  
> those terms, "prairies" have large treeless areas with occasional,  
> scattered trees, and "savannas" have widely spaced trees, but with  
> mostly prairie species growing between (lots of light).  "Woodlands"  
> are denser, and "forests" are the most dense.)
>
> "Without fire the blackberries will give way soon to Douglas-fir--the  
> climax
>  species--even on the Valley floor. Actually, in my area, grasslands  
> (farms)
>  give way to blackberries only for a few months before they are then  
> succeeded
>  by the ultimate climax species--strip malls and condominiums.  
> Personally,
>  I prefer the blackberries, as I  think that even nasty ole  
> blackberries are better
>  for birds than parking lots."
>
>  Well, I have to disagree with a couple of things here. While fire may  
> be a "tool of choice" in many management situations, other tools may  
> be required in other situations (and likely will not yield the same  
> result as burning).  I'd also like to comment on the climax species  
> mentioned.  Generally, a climax tree species has to be able to  
> reproduce under it's own shade, and Douglas fir cannot (which is why  
> forester's prefer to clearcut it, so new stands can be replanted in  
> full sun; and why they drop their lower branches in closed stands).   
> According to Franklin and Dyrness in their classic, Natural Vegetation  
> of Oregon and Washington, grand fir would be the likely low elevation  
> climax in NW Oregon in most upland areas, as it can reproduce under  
> itself.  There are way many sites where that would not occur, and in  
> general, because of disturbances setting back succession, climax  
> ecosystems (at least in this area) are often referred to as  
> "hypothetical"  or "theoretical."  I have heard botanist's mention  
> that Armenian blackberry possibly may be considered a climax on some  
> sites as nothing else can reproduce under it.  (Of course, kudzu  
> hasn't become established here yet, so that may change.....)
>
> "For an overview of plant succession see:
> http://www.cnr.uidaho.edu/for270/powerpoint/Succession/successn_files/ 
> frame.htm"
>
>  I was interested in seeing that, but only succeeded in loading in a  
> blank frame.  Anyone else get it to work?
>
>  Thanks again, Greg for your comments.  I look forward to more.
>
>  Habitat is where it's at: can't have birds without it!
>
>  Best,
>
>  Bruce Newhouse in Eugene
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