Trees or Scrub, Forest or Damaged Grassland?

What happened to the grass? That’s an odd question, or perhaps Odd*, to ask while driving on the Edwards Plateau. Most people ask about “missing” trees on the Great Plains and High Plains, but grass in the Hill Country? Hasn’t it always had trees, even if many of them are a little short and twisty? Mesquite, lots of shinnery oak and other oaks, some cedar, elm, cottonwood, and a few other trees cover the land. The shade is nice, but not the stands so thick they block the wind and mosquitoes wait to gang up on you. This year, there were also a lot of broken trees and deadfalls laying around thanks to the ice and snow from Snowvid 21. I kept muttering “My kingdom for a chainsaw. And bulldozer. And burn permit. And firewood sale stand. And . . .” You get the picture.

If you don’t know the history of the region, it looks a bit overgrown but not bad. Trees are good, right? The National Arbor Day Foundation and others are strong encouragers of tree-planting. Trees soak CO2 out of the atmosphere, they produce shade (most of the time, mesquite and some oaks aside), some produce things people can eat, birds like them . . . More trees are good, right? Especially native species, because those fit the landscape and climate better than do exotics, and don’t harm the ecosystem.

Um, well, sort of. The problem for me is that I’ve read about the pre-Anglo environment of Texas, and . . . Grass. Grass covered large swaths of what is now Texas, far more so than today. Much of the brushy land was grassy land because of pyro-management by the Indians, and by lightning, and intensive grazing by bison. Trees tended to be confined to stream and river courses, where they were protected from fire and heavy grazing until they grew big enough to tolerate creeping fires and the occasional nibble. When the German settlers moved into the area, they found more grass than trees, although trees certainly existed, enough for a sawmill or two.

The problem was thin soil and drought. And no one understood the need for fire management. European forests are 1) very different from North American, and 2) have not been fire managed since, um, well, I have yet to find anything in the archaeology records about controlled or otherwise burns. The grasslands were steppe or wetland, or both (Hungary), and trees tended to be managed, either by property owners or the state. So the new arrivals plowed, planted, grazed heavily, didn’t burn, and farmed as they best knew how. Some techniques worked, others didn’t. In wet years, all was well.

Then there’s the rest of the time. Overgrazing of the grass allowed brush to move in. Drought favors brush, as does fire suppression. As early as the 1890s, extension agents reported problems with good pasture land becoming brush choked and weedy. Toss in the dry years of the 1917-18, then the 1930s, and especially the 1950s, and grass retreats ahead of brush and then scrub forest. Deer, wild hogs, and some other game species do well to OK in brush, so ranchers shifted to farming game as well as cattle and horses. Even so, you can have too much of a brushy thing.

Given my personal preferences, if I won the lottery and could buy property, I’d do what I could to bring back the native grasses. But that’s just me, and I’d have to buy lottery tickets first. It takes a LOT of work and on-the-ground knowledge to do a good job of clearing out enough trees and brush for grass to return, and then manage things properly after that. Large infusions of cash are also required in the beginning. The benefits can be great, including increased stream flow and ground water, greater species diversity, fewer weeds and noxious plants, and healthier livestock and crops. All it takes is cash, sweat equity, knowledge, and labor.

For a few academic generations, we thought that ecosystems had a “climax state,” an end-goal that once reached, was the ideal final equilibrium point for any given ecosystem. Turns out that’s not true. Land use, climate fluctuations, geologic and weather events (think back to the enormous storm that leveled huge swaths of trees in England) . . . They all cause changes. Fire as a land management tool goes way back in human history, and is partly responsible for the savanah’s in Africa and is very responsible for the grasslands of North America, as well as for some of the forests of North America. The brushy Hill Country is just one possibility, brought about by climate shifts (end of the Little Ice Age) and human land management. A grassy Hill Country is another possibility, with large meadows and pastures ringed by fringes of trees, and tree-lined watercourses.

*Over at AtH, it has become common to use Odd to describe those of us who are eccentric in eccentric ways, inclined toward individualism (“just leave me alone to do my thing, please,”) often bookish, and frequently very knowledgable about unusual and fascinating fields, even if they are not our every-day vocation.