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As we trek into Maine’s woodlands our focus is often on wildlife — birds, mammals and maybe even reptiles and amphibians under rotting logs. In spring we are also drawn to wildflowers. Yet none of these would exist without the ‘framework’ of trees — the essence of forests and life on earth. In this workshop led by Richard Jagels, University of Maine, participants will explore how trees evolved over time and how they developed physiological and bio-mechanical adaptations to fill so many ecological and climatic niches. When wildlife sightings may be scarce, knowing how to ‘read’ the trees can greatly increase our enjoyment in the woods, or even our backyards. To register for this workshop, please contact Michelle at 207-288-1356. This workshop has a $35.00 fee. OUTLINE Two hour morning session in lecture hall provides basis for afternoon walk on local woodland trail. Topics to be covered include the following: Evolution – We explore the evolution of trees on land, beginning with tree ferns and ending with broad-leaf hardwoods. As the earth’s climate changed, some forests lost ground to grasslands; and more recently, forests have been curtailed by human activities. Physiology – Trees process light and moisture in different ways, leading to variations in leaf, stem and crown form and tree position within the forest canopy. Through differences in photosynthetic processes trees adapt to high light or shade, and develop varying branching patterns and life spans. Biomechanics – Wind, snow, ice and gravitational forces shape trees as they grow. We see the response in the development of reaction wood (the basis for weather sticks), adjustments in strength properties, and production of different kinds of branches. In extreme environments trees develop krumholz form. Seasonality – Ancient wood fossils reveal non-seasonal growth patterns – like tropical rainforests today. As earth’s climate changed trees adapted to seasonality in various ways. Some, like evergreen conifers, adapted to harsh climates, where competition was reduced. Hardwoods, like maples and oaks, found divergent ways of competing within the same seasonal cues. Diseases and Air Pollution – Why do some tree species succumb quickly to heart rots while others survive for decades? Why are some tree species very sensitive to ozone while a neighbor species is resistant to ozone but is sensitive to acid precipitation? What insect helps to sculpt ‘wolf’ trees? Global Climate Change – In the coming decades will Maine’s forests change much? Will the change in Maine be more or less dramatic than in other parts of the U.S. or globe?