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Post by meadowview on Aug 18, 2008 13:49:01 GMT
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Post by Brian Barnes on Aug 18, 2008 14:28:07 GMT
Phil, That is absolutely awful.... I can imagine all of the hard work and time that went into propagation and planting the bog out as well. Best of luck to you all, Brian.
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Post by meadowview on Aug 18, 2008 15:05:47 GMT
Hi Brian:
Thanks for the condolences. We haven't planted the bog. This was a natural site that has been open without fire for over 70 years (we've gone back to the old aerials to see). Fortunately, we worked with our partner in Maryland, Arlington Echo Outdoor Education Center, and seed was obtained from the site several years ago for propagation with a state permit. These propagated plants are now at Meadowview and Arlington Echo for eventual repatriation to the the wild.
To be honest, if a natural site in a state natural area could not be protected with ample warning I would be very reluctant to reintroduce these plants back to the site. This damage should never have occurred since the state was warned a year ago that the beaver were damaging the site. Unfortunately, this is typical of what is happening to our natural sites in Virginia and Maryland and underscores the importance of the mission of Meadowview.
Best,
Phil
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Post by BarryRice on Aug 18, 2008 17:48:01 GMT
Hey Phil,
A very sad story. How long was the site inundated?
B
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Post by meadowview on Aug 18, 2008 21:13:19 GMT
Hi Barry:
The bog started going underwater in August 2007 and the dams were not broken until August 2008. In short, bog under water 1 year. The entire pitcher plant population was lost. Rare associates lost include cotton grass and orange-fringed orchid. Cranberry severely damaged but will recover.
Don't count on a seed bank recovery of pitchers either. I guess this will provide a "natural experiment" of short term seed banking for a robust Sarracenia population but not an experiment I would do.
Best,
Phil
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Post by ICPS-bob on Aug 18, 2008 22:47:55 GMT
This is interesting. A natural area destroyed by beaver flooding. Hmmm.
A number of years ago, I worked on forested streams in coastal Oregon that had been recently "invaded" by beavers. The changes in channel morphology, sediment dynamics, and the riparian ecosystem were spectacular. Of course, the contemporary "natural" stream was only in this condition for the past hundred or so years -- that is, since the extirpation of beavers. The absence of beavers resulted in the channel downcutting through sediment that had accumulated behind beaver dams over millenia. The original floodplain with beavers had been wide and flat, composed of fine silt. After the beavers were extirpated, the floodplain was eliminated by erosion and the channel substrate changed from fine silt to cobbles. Within 20 years after beavers again moved into the stream, the floodplain was rebuilding. Over the next century, as the beaver population increases and a robust riparian forest of alder and willow replaces the drier-site Douglas-fir, the area will once again return to the "natural" beaver dominated system.
I also studied an area in northern California that was a large swampy meadow in the 1950s. The beavers were killed off and today that area is a dry forest of Ponderosa pine. The stream that used to meander through the meadow is now a 30-foot deep gully that continues to deepen and drain the groundwater from what used to be the meadow.
That is why I said Hmmm. What is considered "natural" depends greatly on the conditions the area has been subjected to and time frame, such as beavers or no beavers; fire or fire exclusion; conversion from forest to 300 years of cotton field to now returning forest; evolution from pond to bog to forest; etc.
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Post by BarryRice on Aug 19, 2008 15:02:04 GMT
Hey Folks,
My esteemed colleague Bob Z has a long and decorated career in forestry, and I dread to counter him on his own turf. Yet....
...Bob, in your examples you are talking about the re-establishment of the habitat at the community level, after a keystone species like the beaver is successfully reintroduced to the system. That's absolutely true. However, what we're lamenting here (I think) is loss at the species diversity level.
The fact that this wetland is a pocket site, without connectivity to a matrix of other sites, doesn't help!
I'm hoping on that seed bank....
B
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Post by rsivertsen on Aug 19, 2008 16:58:16 GMT
In many cases beaver dams actually increases the bog size after a few years, and the seed from the doomed plants seem to scatter out towards the periphery and re-establish new populations as the surrounding real estate changes ecological niches.
Case in point is Big Pond in Orange County, NY, near where I used to live. This site originally was a small semi forested sphagnum bog with a small stream running through it and several trees emerging all around. After the beavers damed it up, it flooded the entire top of the mountain, drowned the trees, and caused several large floating sphagnum bogs, loaded with S. purpurea, D. rotundifolia and D. intermedia, as well as several aquatic and amphibious Utrics.
- Rich
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