Imagine a world with larch trees in the uplands and dawn redwoods in the flats, and bald cypress trees in the wetlands. This existed in the Eocene (~40 million years ago) when the world was warmer, the treeline was at higher latitudes and altitudes, and carbon dioxide in the atmosphere was more than two times Earth’s preindustrial levels. In fact, in the high Arctic where no trees can survive today, deciduous conifers were as lush in terms of carbon sequestration and bioproductivity as today’s rain forests. Now, imagine a world that is sliding back into the greenhouse after millions of years of relative icehouse conditions.
How can we better understand the role of deciduous conifers in the biosphere and their utility in a warmer world. One “natural” experiment is to use dendroclimatology to infer the response of deciduous conifers to a warmer and wetter world. Secrest Arboretum in Wooster, Ohio has two species of larch trees (Siberian and European) as well as bald cypress and dawn redwood trees. These species are all exotic to Ohio and have been growing in the arboretum in some cases for over 100 years. How do they grow in their new homes? This is the subject
