above: Western red cedar planted under alder.
At Soggy bottom Farm, we often pass a book around that is to be reviewed when those who are interested have finished reading it. The latest book to make the rounds is titled “The Journeys of Trees” by Zach St. George.
St. George opens the book by discussing three orphaned populations of coniferous trees: Torreya taxifolia(Florida nutmeg), Sequoia gigantea (Giant sequoia), and Pinus radiata (Monterey pine). In the geologic past, each of these trees had a wide geographic distribution. But now, there existed only small populations that were seemingly trapped in small ecologic refugia: Florida nutmeg in the bluffs overlooking the Apalachicola River in the Florida panhandle; Giant sequoia in a restricted region of the west-slope Sierra Nevada mountains in California; Monterey pine in a couple of dozen square miles around Monterey Bay in California. With climate change (read global warming) and a decline in the habitability of the tree’s localized niche, and with no real avenue for escaping their geological/ecological confinement, each species was in danger of becoming extinct. However, human intervention has likely changed the fate of these trees. Suitable habitat for Monterey pine was found in the southern hemisphere and coupled with the discovery that this tree is a productive forest species, large plantations of Monterey pine were planted and are thriving in New Zealand, South America, and elsewhere. In addition, the overwhelming majesty and rapid growth of Giant sequoias encouraged timber companies to plant them as part of the reforestation mix in logged-over lands in Northern California; a somewhat cooler and wetter ecoregion than their current refugium and in line with what forest experts say the tree needs. And, it was determined that suitable habitat for Florida nutmeg existed in latitudes north of Florida with the result that botanical preservationists (museums, botanical gardens, universities) established specimen groves of this species in scattered northern locations. In each case, human-assisted migration may have saved the species from its dead-end dispersal path and certain extinction.
A second group of trees discussed by the author is a trio of hardwoods that once dominated the makeup of eastern US forests: American Ash; American Elm; and American Chestnut. These deciduous trees were not trapped ecologically as were the above three populations of conifers, they were disappearing because of rapidly spreading diseases. In the case of the American ash, the disease was infestation by the emerald ash borer, an insect; in the case of the American elm, the disease was Dutch elm disease, a fungus; and in the case of the American chestnut, the disease was Chestnut blight, another fungus. Each respective disease has drastically reduced the populations of these three trees to the point that they are no longer important components of eastern hardwood forests. In each case, the disease agent causing the tree’s demise was introduced to the American forest by inadvertent human-assisted migration. Humans accidentally moved the organisms responsible for each disease from the organism’s home ground in Asia to the U.S. The stories of these three diseases and the sad tale of the pestilence wrought by the European gypsy moth in causing damage to a great many forest-tree species were used by St. George to elucidate the unanticipated and unwelcome effects that can come from human movement of species from one geographic area to another. Whereas human-assisted migration may have been the salvation of some tree species, it was unquestionably the cause of the demise of other species.
St. George goes on to discuss the many things tree scientists and foresters are doing to counter the ills that are plaguing our forests, i.e., finding alternative ecosystems to support those trees that seem to have migrated into ecological dead ends; introducing biological control measures by treating the forest with the biological enemy of the disease-causing organism, and genetically modifying susceptible trees to produce tree stock that is resistant to the disease. Each measure requires intense large-scale effort and success needs be viewed in terms that accept only partial mitigation.
The author ends the book with an inquiry into the motivation and rewards of the individual act of planting a tree. The motivation for a tree planter is the sense that in planting a tree he/she is in some way doing something good, doing good for the long term. This is whether the planter is a participant in the worldwide UN tree planting campaign Plant-for-the-Planet, to buffer some of the causes of global warming, or acting as a conservationist by planting a native tree species to stabilize soil, provide native habitat, and block the spread of an invasive species; or planting a forest seedling in a commercial woodlot to establish the root-stock for a future wood-producing economic resource, or planting an orchard seedling to establish fruit-bearing trees for future food-producing capital, or planting to create an environment that makes one feel better, or planting to leave a legacy. In all cases, the outcome benefits mankind in some way. This is true even though the time frame between planting and the realization of the tree’s productive good is, for the most part, longer than the expected life span of the person doing the planting. Thus, the planting of a tree is an altruistic act of faith that the world can be made better in the long term through the agency of trees.
How do the messages in this book relate to Soggy bottom Farm? In a nutshell, Ellen and Jay plant a lot of trees. They plant them for all the reasons that Zach St. George enumerated in his book. They plant them for the love of planting trees, for the joy they get from watching them grow, and for the vision they have of the legacy those trees will leave for Leo and Ivan. With 17 acres of heavily wooded forest, there is no need for more trees on the farm. There is only a desire for more trees because the farm can accommodate more and a compulsion for participating in an endeavor that will make the world a better place.
above: Doug fir and birch plantings