Thursday, May 31, 2012

When Ecosystem Restoration goes Wrong

The photos above were taken in mid-May, a time of year when ground flora peaks in all its greenness and freshness. I took the photos this May to show what happens when an agency burns a woodland really hot without thinning beforehand and without managing a pitiful deer overpopulation problem. Oh, I'll hear complaints about posting sad photos like these, but I need to say it: not all prescribed fire is good prescribed fire. I think I've been through this before on this medium, but I guess it's time to reiterate: when dealing with horribly damaged systems like we have in the Ozarks, when trying to restore a rich grass/forb mix to the woodland matrix, you have to look for indicators that your fire is well placed. If you have a patch of woods with nothing but leaf litter on the ground, and you know the area hasn't been grazed to hell by domestic livestock, sure, try burning it once under moderate conditions to see what happens. However, if you've burned before and nothing comes up but oak bushes (due to grazing by domestic livestock), or ground flora comes up and the deer clip it off immediately, for heaven's sake, don't burn again with such an intensity that you cook the soil. I have been back to this site in late May, and it looks exactly the same. Oh, there was one Desmodium rotunidifolium poking through the black soil, but the single plant had been hit pretty hard by deer. Considering that there are few in the field of natural history actually monitoring the impacts of our deer problem (as it relates to biodiversity), or monitoring fire effects in damaged systems, images like this will become common across the landscape.

On the other hand, if the woods pictured above only had a deer problem, the ground flora would be represented as a monoculture of sedges. The woods above have obviously had a significant grazing history, resulting in a dense thicket of red oak/black oak (all even aged and suffering from synchronous cohort senescence)that calls for a serious need of hardwood thinning if a rich ground flora response is desired.

The above photos were taken from one small 5 acre glade down in the White River Hills. The folks in charge down there have been encouraged to avoid burning huge piles of cedars in one place; instead, place them in windrows or burn them in smaller piles when they're still green so you don't kill the soil beneath. No, no instruction taken, so these dead soil areas are the result of massive campfires evenly spaced across the glade because the managers didn't burn cedar slash during red needle stage and instead waited until the logs would catch (dry fuel conditions). But rather than making one big campfire and feeding the logs into that one campfire (which would result in one of these dead soil areas), managers here made 10-20 campfires with cedar logs, thus making so many dead soil areas that it's challenging to run a sampling transect 50m. long across the glade. These dead soil areas will remain this way for at least ten years, only to be occupied then by ruderal species like ragweed. Not good for the sampling frame, and not good for the glade ecosystem and the biota that depend on it.
The above photos were taken on a glade in July 2011. Both of these photos illustrate what happens when the cedars are cleared from a glade and no fire is implemented. With the long history of grazing by domestic livestock on most glades in Missouri, the glades turn into brush piles--good for yellow-breasted chats, but death to glade flora that depends on light and fire. The second photo shows one of the large bonfires erected on a glade that was burned in place and consequently left a huge scar on the landscape. Ecosystems are fragile, and they've managed to persist through 200 years of abuse by human inhabitation, grazing, and neglect. The least we can do as ecologists and as land managers is to implement sound restoration efforts that are guided by scientific knowledge and experience. We should not be experimenting with such detrimental tools on these landscape types that are already threatened by encroaching development and isolation. If you're going to restore a glade, follow up with recurring fire under proper conditions. If you have to make a burn pile of your cedars because you haven't burned regularly out of neglect, make it in one central location and don't scatter towers of logs all over the glade. If you're burning woodlands, know when you're dealing with a damaged landscape and use the appropriate tools. Aerial spraying with herbicide to knock out deciduous woodlands in favor of pine is a terrible idea any way you spin it.

I could go on with photos and nightmare situations that occur regularly in Ozark ecosystems, but I won't. At least maybe these few photos will help you recognize when restoration efforts are misplaced and implemented incorrectly.

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