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Pines

Enlightened Forestry

Tree conservationists have learned that when forests are eliminated, the trees that grow back are seldom the same ones that were there before. The pine trees felled in Michigan in the late nineteenth century never grew back, and were replaced by oaks and aspens, which the gypsy moth is fond of. The hardwoods in the southern part of the country were cut to make room for pines that could be harvested 20-40 years later. There are now pine plantations from North Carolina to Arkansas, where the trees frequently do not grow as rapidly as had been planned.

Today, enlightened foresters practice sustainable forestry, a practice that places nature ahead of timber harvests, and removes tree from the forest at a rate that can be maintained indefinitely. Models for returning land to forest come from the old stands of unmanaged forest, which have sustained themselves for thousands of years.

Resources

Books

Lannenner, R.M. The Pinon Pine: A Natural and Cultural History. Reno: University of Nevada Press, 1981.

Margulis, L., and K.V. Schwartz. Five Kingdoms. San Francisco: W. H. Freeman and Company, 1988.

Pielou, E.C. The World of Northern Evergreens. Ithaca, NY: Comstock Publishing Associates, 1988.

White, John, and David More. Illustrated Encyclopedia of Trees. Portland, OR: Timber Press, 2001.

Other

Chaw, S. M., et al. "Seed Plant Phylogeny Inferred From All Three Plant genomes: Monophyly of Extant Gymnosperms and Origin of Gnetales from Conifers." Proceedings of the National Academy of Sciences of the United States of America 97 (2000): 4086-4091.

Peter A. Ensminger

Randall Frost

KEY TERMS

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Cuticle: —Layer of wax covering the surface of leaves and other plant parts.
Dendrochronology: —Scientific examination and interpretation of tree rings.
Diploid: —Nucleus or cell containing two copies of each chromosome, generated by fusion of two haploid nuclei.
Fascicle: —Bundle of leaves, in the pines often associated with a fascicle sheath, a special tissue at its base.
Fertilization: —Union of male and female sex cells to form a diploid cell.
Haploid: —Nucleus or cell containing one copy of each chromosome.
Pollination: —Movement of pollen from the male reproductive organ to the female reproductive organ, usually followed by fertilization.
Strobilus: —Reproductive organ consisting of modified leaves (sporophylls) spirally arranged about a central axis, colloquially referred to as a cone.

Additional topics

Science EncyclopediaScience & Philosophy: Philosophy of Mind - Early Ideas to Planck lengthPines - General Characteristics, Evolution And Classification, Life Cycle, Economic Importance, Bristlecone Pine, Pine Cones