Tuesday, November 04, 2008

Abierto? Cerrado.




In the unseasonably mild weather of June and July, I spent time in the White River Hills mapping the terrestrial natural communities of a large, uninterrupted patch of woods. I saw several plants I hadn’t seen before (big populations of the stunning Aster linariifolius), scrambled up my share of steep limestone benches, down draws and hollows, and across undulating belts of glades. I stood at the woodlands’ edge contemplating the rules of engagement: am I looking at a degraded, closed dry-mesic woodland or a fragment of actual forest (a community that shows up infrequently in Missouri)? Would fire willingly, naturally run through this patch of woods? What about the soil composition and moisture, geology, grazing history, aspect, slope, topography, ground flora, canopy (and on and on)?



I wrote about the tedious nature of this project back in June or July, focusing on the parameters that determine terrestrial communities. Early on in the project, I almost gave up, daunted primarily by the challenges posed by degraded woodlands mimicking forest. I finally figured it all out, thankfully, and can somewhat confidently distinguish between woodlands and forest in various stages of restoration and degradation. So, last week, I ventured to the other side of the Ozark Highlands looking for restored, degraded, and restorable woodlands, wondering if I could tell the difference between them all.



The lower reaches of the Current River Hills and Eleven Point River valley include thousands of acres of sandstone and chert woodlands. Shortleaf pine dominates the landscape in acreage primarily owned by the federal government. Heading southeast out of Van Buren, our guide promised to show us woodlands in various stages of restoration: woodlands that have been regularly burned, woodlands that need to be burned more, woodlands that should be thinned and burned, and sad woodlands with no treatment at all (mainly trashy old clearcuts that haven't had any management whatsoever).



Right off the bat, it was pretty easy to tell which areas had been treated with management and which areas had (essentially) been neglected. Thick, dense stands of trees with no understory told the story of fire suppression. Mile after mile of formerly open woodlands and savanna, now overgrown, overstocked, degraded and closed to all light. While the designation of forest implies a depauperate understory, a well-developed midstory and closed canopy, the degraded and closed woodlands that perhaps had the same low light requirement as a forest was clearly not a true forest. Fire wanted to go into these places. The roadsides leading up to the closed woodlands wasn’t populated by ferns and gingers or other forest plants hanging onto the edge, but tall bunches of little bluestem, growing so close together to make the right of way almost impenetrable to the average girl with two legs. With light made available by a roadcut, the woodland understory- grassy, full of goldenrods and asters- thrived. And with a little fire and thinning, the surrounding closed woodlands could be opened up to light, thereby allowing suppressed grasses and wildflowers to return to the understory making it a nice, open woodland.



The leader of the fieldtrip didn’t have to say a word when we entered a management area that had been burned five times in ten years. The open stands of pine trees and grassy understory spoke for itself. Because prescribed fire is unlike natural fire events (which burned until they ran out of fuel or were squelched with rain or snow), demarcation lines illustrated burned and unburned areas rather effectively. On one side of the road sat managed woodlands with Solidago odora (whose leaves smell like Dutch licorice candy), sweet everlasting, and Aster patens (a nice, quality woodland plant that I think I've shown about 80 times in the past year) growing among little bluestem. Twenty feet away across a graded road were impenetrable acres of maple, oak, scattered pine growing among nothing but leaf litter. But the roadsides next to the overstocked woods, those areas where light could reach the ground, were rich with diverse woodland plants.



We continued on the fieldtrip, driving through open, open, open woodlands and then closed, closed, desperately-wanting-to-be-open woodlands, what with woodland edges filled with wildflowers and grasses. We learned that a little restoration goes a long way in Missouri’s woodlands. The healthy systems we witnessed hadn’t been burned as regularly as they would have been if, say, they were owned by The Nature Conservancy, but they’ve been burned at least twice in ten years. (Of course, The Nature Conservancy probably doesn't own a single acre of lousy woods in the state of Missouri. They have crews and funding to burn on schedule, weather permitting. They always possess great woods.) The potential for woodland restoration is there in the lower Ozarks, the seedbank is there, waiting, and the energy is there with full time federal staff wanting desperately to set fire to these areas. If appropriate funding and good burn weather windows find their way to the lower Current River Hills, these closed woodlands will gladly, easily, happily open.


See, interspersed among the text, a single picture at the top of a closed woodland that makes my chest hurt, followed by pictures of open woodlands that make me say "ah....that's nice." I've included one with Erianthus alopecuroides (tall, bushy seedhead grass) in the foreground. Known from only a few counties in Missouri, E. alopecuroides appeared on a roadside after a pine woodland burn. Sweet everlasting in seed in honor of my colleague who always crumbles the flowerhead of this plant in his hand to inhale the interesting scent. And finally, a hopefully illustrative image showing an open pine woodland with a closed woodland across the gravel road.

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