Ecosystem lost and found?

Looking for Longleaf. The Fall and Rise of an American Forest by Lawrence S. Earley (2004) Chapel Hill. University of North Carolina Press. 322pp.

When I was a teenager, my grandfather recalled for me how the longleaf pine forests in eastern North Carolina looked when he was young, some seventy to eighty years before. It was like being in a cathedral, he said, with the trunks of the trees like columns and the forest floor clear as far as you could see. This book gives an introduction to the character and extent of the longleaf pine ecosystem, once dominant over a vast region of the Atlantic and Gulf Coastal Plain, introducing the plant, Pinus palustris, the diversity of associated plants (sometimes hundreds of species in a square kilometer and as many as 40-60 in a square meter) and several of the more distinctive animals, like gopher tortoise and red-cockaded woodpecker.

Earley explains the critical role of fire and soil in establishing the diversity of types within the overall longleaf ecosystem.

The middle part of the book is a historical account of the European encounter with the forest, its exploitation by the naval stores industry and its eventual destruction by that industry and the railroad based loggers. Some of these descriptions fit closely with what I heard from my grandfather and from a friend in North Carolina (whom Earley interviewed for the section on turpentining). He talks about rafting logs down the coastal rivers (as my grandfather, born in 1869, did as a boy) and shipping naval stores (my grandfather also described how the cooper made the barrels for turpentine). He explains that what preserved so much of the forest were the limitation of cutting timber to areas close to usable streams, that is until the railroads came. My father (born 1913) recalled how the railroad was brought in to log some of the most remore and inaccessible places when he was growing up. Some time around 1970, before the railroad was finally abandoned, I saw carloads of longleaf pine stumps waiting to be hauled off to extract the valuable resins or to make fatwood kindling, sold by L.L. Bean, among others. Earley also mentions the continued interest in salvaging sunken logs and getting lumber from old buildings.

The final chapters are on the development of forest management ideas, from failed attempts at replanting to replacement by loblolly and slash pine and the gradual development of methods to regenerate longleaf, first as even aged stands but now moving towards uneven age management and overall ecosystem restoration. Red-cockaded woodpecker played a key role in several changes in policy, driven by court decisions under the Endangered Species Act. Many of the agencies involved, like the US forest Service have serious problems dealing with the steady increase in scientific and ecological understanding of the forests. Institutional change is difficult, especially when institutional memory is impaired by frequent reassignment of key people and political pressures. The US Forest Service has had an especially hard time admitting it has been wrong about fire suppression and even-aged management.

He talks about the role of national and state forests and of large and small private landholders (currently there is increasing longleaf acgeage on federal and maybe state land and on large private conservation holdings, but continued losses on timber company lands and small private holdings) and what the trends may mean for the future of the ecosystem and many of its species. New incentives under the Conservation Reserve Program may be changing the minds of some private owners. It is possible to derive a pretty steady income from restored longleaf, partly through sale of raked needles in the 10th to 15th years after replanting. Poles are much in demand, using middle aged trees. The author seems most impressed by adaptive management approaches using small group-selection cuts and frequent growing season fire. Several interesting examples are described in the next to last chapter on restoration. Some of these areas sound like they would be worth seeing, and there are some groups that can help with restoration, a topic that is on my mind lately, as I and my brothers and sisters still hold a small remnant of thousands of acres of longleaf land owned by my great-great grandfather in the early 1800s. We will soon be clearing the stand of loblolly pine, planted decades ago, to make way for longleaf again.

Neotropical travellers

Essay on the Geography of Plants, by Alexander von Humboldt, and Aimee Bonpland. 2009 (1807). Edited by Stephen Jackson. Translated by Sylvie Romanowski. University of Chicago Press. Chicago. 274 pp with tableau in pocket
This book is pure descriptive natural history, with almost no speculation or discussion of causes. It is divided into Humboldt’s Essay of some 30 or 40 pages and the longer Tableau Physique prepared by Humboldt and Bonpland. Some of Von Humboldt’s fascinations, like barometric pressure, which he includes along with temperature, humidity and “electrical tension” as factors influencing plant distribution, seem peculiar to me, but I have to remember that he was much more limited in what he could measure than we are today. Another peculiarity is his notion of “social” plants, by which he seems to mean those that form dense monocultures as opposed to mixed stands. He says these live “in organized society, like ants and bees…” His examples include mangroves, Cladonia lichens and pines, but also Vaccinium. He notes that such plants are more common in the temperate regions than in the tropics. Mexico is an exception, harboring many temperate species, like pine, oak and sweet gum, which he attributes in part to the vast geographical expanse of the northern part of America, narrowing southwards. Somehow this causes Mexico to be colder than similar latitudes elsewhere. Then there is his idea of “subterranean vegetation,” which seems to mean fungi in caves and mines. He treats these “cryptograms,” alongside lichens and mosses. How aware was he of the fundamental distinction between autotrophs and heterotrophs? Photosynthesis was barely beginning to be understood in his time.
He also lacked a clear notion of geologic time, referring only to remote ages, but with no sense of the scope and significance of the fossil record. Only the epoch of human spread across the earth is accessible to his reflections on the distribution of plants. When compared to Graham’s Natural History of the New World, he has far less to go on, and barely any sense of the potential of fossils to shed light on modern plant communities and their distributions. Yet Graham clearly is following in the footsteps of von Humboldt and Bonpland.
One advance he makes is to point out the importance of physiognomy alongside taxonomy in describing communities of plants (another of his ideas) what we today commonly call life forms or growth forms.
The main thing, though, is the Tableau Physique, the profile of the Andes, using the volcano Chimborazo thought, at the time, to be the highest peak in the world. The detailed data packed into a single illustration is startling and quite beautiful. The other wonderful part is his concluding reflections in the essay on the value of natural history writing and artwork in elevating and liberating our understanding, even if we cannot experience these amazing places directly.

New world history

A Natural History of the New World. Ecology and Evolution of Plants in the Americas, by Alan Graham. 2011. Chicago. University of Chicago Press. 387 pp.
This is an ecological and evolutionary story acted on the stage of two continents from the close of the Mesozoic to the recent. South America starts out isolated or nearly so, while North America begins joined to Eurasia across the proto-Atlantic. It ends with two continents joined by a narrow isthmus and a sporadic connection to Siberia across the Bering Sea. During this time as the Americas override the Pacific plates, a series of great mountain ranges form along the western edges of both continents, altering the directions of rivers and radically altering the climate of the continental interiors. Late in the period, the shift towards glacial climates turns what were temperate climates under a polar insolation regime into boreal forest and tundra, with deciduous forests to the south and new dry ecosystems in the arid west.
It is a dramatic story, with a shifting cast of characters, most impressively the higher angiosperms and the radiating mammals responding to each other as well as struggling among themselves to dominate under the shifting conditions. The rise of groups like the grasses and the ungulates with their associated carnivores are among the most visible and dramatic developments, if not quantitatively as significant as the insects and fungi, which changed much less over the same time. This is a vexed question; megafauna and keystone species enthusiasts on the side of top-down regulation and ecosystem engineering, those of us who look at energy flux and nutrient cycles as keys to ecological processes and who see microbes as the dominant force, alongside plants, on the bottom-up side. Probably both views are right some of the time. No doubt, though, that climate and geology – lithosphere, atmosphere, hydrosphere – are the ultimate regulators, although the biosphere’s impact on carbon cycling is also significant.
This is a very detailed book, giving an account of dozens of types of communities both in the past and the present vegetation of the Americas. It also describes the phases of development step by step, tracking the geologic changes and the shifting vegetation as revealed by pollen and macro fossils. The author is a noted paleobotanist at the Missouri Botanic Garden. There are good photos, maps and graphs of changing temperatures over the epoch. Truly a history of nature.
Graham also has excellent chapters on the techniques of paleoclimate reconstruction and the collection and interpretation of fossils. The text is also a wonderful travelogue, full of historical and prehistorical anecdotes, and covering the modern biogeography of the new world as well as the story of how it came to be as it is.