Back to What?

My first visit to Reed-Turner Woodlands Nature Preserve turned up this beauty:

Condylostylus patibulatus, Reed-Turner Woodlands Nature Preserve,
Lake Co, IL 6/8/2014

This is Condylostylus patibulatus, as far as I can tell. It's a member of the family Dolichopodidae, or Long-legged Flies. Despite it's tiny size and gleaming appearance, it's a voracious predator of truly tiny insects!

Today, though, it's an excuse to discuss something else: this sign, or rather the thinking behind it.

Reed-Turner Woodland Nature Preserve,
Long Grove, Lake Co, IL 6/8/2014

Seeing this brought a natural question to mind -- what is a "low-quality tree"? In this case, I suspect that European Buckthorn was a major player. But the very idea of high- vs. low-quality plants and animals says something important about us as conservationists (and indeed, as people). When we are managing a piece of land, we have an idea in mind of what that landscape is supposed to look like, and how it's supposed to function. Where do we get those ideas?

In a recent post, I discussed the use of fire to maintain our local prairies and oak woods. What I never discussed there was why we would want to maintain those environments. Why not allow our prairies to grow into forests, and our oaks to be replaced by maples?

A seemingly common viewpoint in this regards is that we want a "natural" landscape. So, to maintain this landscape:


Spring Bluff FP, Lake Co, IL 5/25/2012

We practice this:


Prescribed Burn, Illinois Beach SP, Lake Co, IL 11/17/2011

I actually discussed this with a local biologist once, and he remarked that he was attempting to mimic a "non-anthropogenic" landscape. (We were actually discussing the timing of controlled burns, not the advisability of them.) But that reminded me of a minor epiphany I had several years ago -- in Lake County, outside of perhaps a few bogs, there is no such thing! The last glacial maximum ended 10-12,000  years ago. Yet we know that paleo-indians were in North America at least 14,000 years ago, and probably even more. Carbon-dating of remains from a mammoth kill site in Kenosha Co, just north of here, suggest human presence back to 14,500 years ago right in this area. (1) I don't know the history after the glaciers receded, but it seems unlikely that humans took more than a few thousand years to move in here. So our landscape has had humans living on it for thousands of years! And one thing we know about the Indians just pre-Colombus is that they used fire to sculpt the landscape at a scale we have rarely felt brave enough to attempt.

So back to my question: why maintain these environments?

With all of the intercontinental travel we indulge in these days (as a species, anyways!), many of the "low-quality" species we're discussing are introduced from elsewhere. What that means in this context is that if we simply sit back and allow our landscapes to change as they will, eventually they'll look the same as everywhere else on Earth (climate permitting, anyways). So one answer to my question is that we work so hard in order to maintain the unique quality of our landscapes -- once they're gone, they could be gone forever.

Another answer is that in an ever-changing world, most of the natural landscapes we are likely to encounter are fairly stable, and that means that they work well in terms of nutrient cycling, water cycling, etc. Those processes are called ecosystem services when they benefit us, and preserving ecosystem services should be a primary concern of anyone who manages a large-scale landscape. Since stable landscapes already preserve those services, they are good things both to keep and to study. If we allow those landscapes to change too fast, we lose that model and we may lose the services directly as well.

One last answer is that we work to maintain those environments because of our attachment to history. We like to know how things used to be, whether it's human society or the environment we carved those societies out of. Reading about the arrival of the Mayflower is interesting stuff, if presented correctly. Imagine how much more interesting it might be if you could go there and see what Plymouth Town looked like as they came ashore!

That ideal is lost for Plymouth, or Baltimore or Roanoke. But if you want to better understand the pioneers' journeys to Oregon, you can go out to Wyoming and stand in the very wheel ruts laid down by the covered wagons, and look out over a landscape that has only changed in the details. Around here, you can't see a broad prairie running between distant oak openings, but there a few little patches where you can see what an oak opening would have been like, and ponder the wonder of a pioneer kid finding his first deer wandering through one.

(1) http://www.kenosha.org/wp-museum/exhibits-2/mammoths-kenosha-public-museum/