Prairie/savannas: restoration or reconstruction?
We generally use the term "restoration" to refer to what we are doing. Sometimes the noun is modified into "ecological restoration".
Sometimes the word "reconstruction" is used instead of "restoration". The Minnesota DNR, which publishes a nice handbook on prairie restoration, makes this distinction: reconstruction refers to establishing native plants on a site that has been completely degraded, so that there are no prairie plants left. This site might have once been a prairie, but if so, it was a long time ago, and agriculture or forestry has destroyed it.
Restoration, on the other hand, refers to starting with an existing remnant, a piece of land on which native plants still remain, although likely in a degraded condition. Restoration involves "improving" the native plant community, using techniques such as invasive plant removal, reintroduction of fire, and planting seeds or seedlings to supplement the existing species. The end results in both reconstruction and restoration might be the same, although in most cases it takes a lot less time to restore than to reconstruct.
Although this distinction may seem a bit pedantic, since the goals are similar, the techniques are usually quite different.
At Pleasant Valley Conservancy, we have done both reconstruction and restoration.
Reconstruction: The four ag fields (Toby's, Pocket, Valley, and Ridge Prairies, now in the Conservation Reserve Program) had been in agriculture so long that there was nothing "good" left. The vegetation was principally smooth brome grass, with impressive amounts of invasive weeds including annual weeds, as well as such perennials or biennials as birds foot trefoil, ox-eye daisy, Queen Anne's lace, sweet clover, and wild parsnip. Two other "fields", the Crane Prairie and East Basin, had apparently never been plowed, but through the years had become heavily wooded. Again, the work was reconstruction, but starting with chain saws. In both cases, the final step before planting involved heavy applications of glyphosate herbicide to kill all existing plants.
Restoration: On the other hand, the south-facing slope and all of the savanna areas at Pleasant Valley Conservancy were restored rather than reconstructed. Considerable chain saw work was required, to remove both invasive shrubs and trees. However, many "good" native plants were present and not only thrived, but increased greatly after the woody invaders were removed. Since years of degradation had led to an impoverished native flora, many new species were introduced by hand planting, a technique called "interseeding".
One nice thing about the restoration work is that many surprises took place. Species that we did not know were present arose after clearing and burning, some of them quite rare. On the other hand, no surpise species occurred in the reconstructed prairies. What we planted was what we got, and nothing else.
The best manual on restoration techniques is "The Tallgrass Restoration Handbook" by Stephen Packard and Cornelia Mutel, published in 1997 by the Island Press, Washington, D.C.
Sometimes the word "reconstruction" is used instead of "restoration". The Minnesota DNR, which publishes a nice handbook on prairie restoration, makes this distinction: reconstruction refers to establishing native plants on a site that has been completely degraded, so that there are no prairie plants left. This site might have once been a prairie, but if so, it was a long time ago, and agriculture or forestry has destroyed it.
Restoration, on the other hand, refers to starting with an existing remnant, a piece of land on which native plants still remain, although likely in a degraded condition. Restoration involves "improving" the native plant community, using techniques such as invasive plant removal, reintroduction of fire, and planting seeds or seedlings to supplement the existing species. The end results in both reconstruction and restoration might be the same, although in most cases it takes a lot less time to restore than to reconstruct.
Although this distinction may seem a bit pedantic, since the goals are similar, the techniques are usually quite different.
At Pleasant Valley Conservancy, we have done both reconstruction and restoration.
Reconstruction: The four ag fields (Toby's, Pocket, Valley, and Ridge Prairies, now in the Conservation Reserve Program) had been in agriculture so long that there was nothing "good" left. The vegetation was principally smooth brome grass, with impressive amounts of invasive weeds including annual weeds, as well as such perennials or biennials as birds foot trefoil, ox-eye daisy, Queen Anne's lace, sweet clover, and wild parsnip. Two other "fields", the Crane Prairie and East Basin, had apparently never been plowed, but through the years had become heavily wooded. Again, the work was reconstruction, but starting with chain saws. In both cases, the final step before planting involved heavy applications of glyphosate herbicide to kill all existing plants.
Restoration: On the other hand, the south-facing slope and all of the savanna areas at Pleasant Valley Conservancy were restored rather than reconstructed. Considerable chain saw work was required, to remove both invasive shrubs and trees. However, many "good" native plants were present and not only thrived, but increased greatly after the woody invaders were removed. Since years of degradation had led to an impoverished native flora, many new species were introduced by hand planting, a technique called "interseeding".
One nice thing about the restoration work is that many surprises took place. Species that we did not know were present arose after clearing and burning, some of them quite rare. On the other hand, no surpise species occurred in the reconstructed prairies. What we planted was what we got, and nothing else.
The best manual on restoration techniques is "The Tallgrass Restoration Handbook" by Stephen Packard and Cornelia Mutel, published in 1997 by the Island Press, Washington, D.C.
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