Tree Health and Physiology in a Changing Environment
Abstract
A tree is a large, long-lived, perennial, compartmented, woody, shedding, walling plant. This definition is based on new tree biology concepts (Shigo, 1986a,b, 1991) and explains much about how mature trees function through their unique structure. When the tree begins its life, it is mostly leaf in mass (Fig. 7.1a). As a tree grows in stature, it becomes mostly stem in mass and the foliage represents only a few percent of the total mass. Roots remain relatively constant at about one-fifth the total mass as a tree grows from a small sapling to a mature standard in the forest canopy. Branches represent only a small fraction of total mass, which decreases over time, as older branches are shed. Also shed are leaves, roots, and outer bark. However, aging wood cannot be shed, but dies internally as sapwood is transformed into a core of protection wood, often called “heartwood” (Fig. 7.1b,c; Table 7.1).
Department
Biological Sciences
Publication Date
1-1-2000
Journal Title
Ecological Studies
Publisher
Springer New York
Digital Object Identifier (DOI)
Document Type
Book Chapter
Recommended Citation
Shortle, W.C., Smith, K.T., Minocha, R., Minocha, S., Wargo, P.M., Vogt, K.A. (2000). Tree Health and Physiology in a Changing Environment. In: Mickler, R.A., Birdsey, R.A., Hom, J. (eds) Responses of Northern U.S. Forests to Environmental Change. Ecological Studies, vol 139. Springer, New York, NY. https://doi.org/10.1007/978-1-4612-1256-0_7
Rights
© 2000 Springer Science+Business Media New York