Saturday, February 09, 2008

Pinus echinata

Before the 1880s, Missouri’s Ozarks were a very different place than they are today. Then, shortleaf pine and pine-oak woodlands occupied 6.6 million acres of the eastern Ozarks, down around Shannon, Taney, Carter Counties. Pine woodlands supported a rich understory of little bluestem, blueberry, a whole host of wildflowers and the occasional oak sprout. The latter part of the 19th century introduced the lumber industry to the Ozarks and, with that introduction, came the utter destruction of the pine woodlands. Between the late 1880s and the early 1920s, millions of acres of shortleaf pine were removed from Missouri. Obviously, the parent seed material was cut, so pine never regenerated after the devastating overharvest. Instead, red and black oaks moved in to occupy the high ridges and acid soils where pine should be today.

Timber harvest in the Ozarks at the turn of the century wasn’t nearly as resolute as it was in southeast Missouri, where nary a cypress or oak was left in the wake. As lumber prices dropped in light of the Depression, several thousand acres of shortleaf pine were spared. Traditionally, shortleaf pine occurred in those fantastic dry chert woodlands that I appreciate so deeply and ramble on about. Historically, shortleaf pine occurred on rolling or dissected hills, and almost solely on the Roubidoux formation of sandstone which produces acid soils. The historic populations of shortleaf pine were directly linked to -you guessed it- the soils, the hillslope (topography impacts fire frequency, after all), the climate and the associated fire history.

The abundance of pines in the Ozarks was largely due to mixed intensity fires, which ripped through the area at 10-20 year intervals. During the timber harvest and in the years following the deforestation, fire was suppressed in an effort to reforest the clearcut areas. Areas once rich with shortleaf pine morphed into oak woodlands and forests with an undeveloped understory. Landowners introduced grazing to these second growth oak woodlands. Without fire, with too much timber harvest, and the added stress of grazing, open stands of pine with their requisite bluestem understory almost ceased to exist in Missouri. Even now, if fire is not applied to the existing stands of shortleaf pine, Missouri’s pine population will occupy a mere 10% of the landscape rather than the historical 53% in a matter of years.

Luckily, Missouri is home to a whole suite of land managers who work assiduously to maintain our pine and pine-oak woodlands. After the timber industry obliterated their own crop source, foresters planted thousands of acres of shortleaf pine trees throughout the lower Ozarks. In the late 1920s and 1930s, landowners with shortleaf pine on their property were encouraged to sell their seeds to foresters to help out with the reforestation efforts. Today, some of these pine plantations are managed as if they are native landscapes. Unfortunately, the rich understory associated with pine woodlands had been so mangled by tilling and other disturbances, that these plantations hardly resemble an undisturbed pine woodland. That the trees are planted in vague rows doesn’t help, either.

Nevertheless, with lots of management, lots of fire, and yes, reforestation efforts, shortleaf pine is in resurgence. My colleague who said that pine would be better suited for warmer climates? He’s not all wrong (if there was enough land, fire, and a massive oak die-off). Drought and warmer temperatures will help pine trees in the Ozarks. During winter months, which will be wetter and warmer in light of climate change, pines will be able to photosynthesize, giving them a stark advantage over deciduous trees. If the summers produce drought, pines will have the advantage because they have the ability to grow during the warmer winters. Increased carbon dioxide levels seem to benefit pines, based on a study through University of Missouri. However, speculation holds that higher carbon levels will harm the understory, the plants that make up the rest of the pine woodland complex. Because landscapes are so intricately linked, with all plants and animals playing important roles, we don’t know how the pines will fare. If the pines thrive but their components falter, the whole landscape might collapse.

A good portion of the state’s pine woodlands are in the careful hands of three awesome land managers who will make certain that they thrive, who will make certain that they will be as strong as possible in light of climate change. If you’re anywhere around Licking, check out the Peter A. Eck Conservation Area, located 12 miles northwest of Licking along the Big Piney River. A state designated Natural Area, part of this CA preserves a wonderful 254 acre tract of dry-mesic chert woodland, a glimpse into the lower Ozarks before the 1880s.

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