The explosive growth of human population is changing the earth dramatically. Only by understanding how human activities affect our environment can we predict global climatic changes. Scientific studies of these changes and their effect on natural ecosystems and crop production are crucial to the future of our society.

Other environmental issues, such as pollution, also interest botanists. Many plant species are especially sensitive to certain pollutants. Botanists study the effects of different types of pollution on plants. They use their results to advise lawmakers on legislation for environmental protection and on ways to save priceless natural areas.

Plants are chemical factories - plant biochemists are engaged in identifying and purifying potentially useful chemicals produced by plants. Many of the drugs listed in the U.S. Pharmacopeia are still obtained from plants or derivedfrom plant products.

Photo courtesy of Marsh Sundberg.

By using plant tissue culture, botanists can grow entire plants from single cells. This has exciting potential in biotechnology, horticulture, forestry, and plant pathology. For example, the stately American chestnut was once a widespread tree in our Eastern forests. Today it has virtually disappeared because of a disease-producing fungus that causes chestnut blight. The American chestnut recently has been grown in plant tissue culture. If we can develop a blight-resistant strain of American chestnut, we will be able to propagate disease-resistant trees very quickly. These trees could then be planted in our forests and the American chestnut would once again be one of our most important hardwood species.

Plants are chemical factories. Many of the chemicals that they produce are useful to humans. Besides food, plants provide raw materials for paper, building materials, solvents and adhesives, fabrics, medicines, and many other products. Botanists study the chemicals produced by different plants to find new uses for them. For example, we use some plant chemicals to treat certain types of cancer.

The earth's biological diversity, or the kinds of organisms that populate the earth, is decreasing. As humans change the environment for their own purposes, plants and animals living in these areas become increasingly endangered. Plant taxonomists and plant ecologists work to identify and understand new plant species, especially in such biologically rich areas as tropical rain forests. Plants of the rain forests are important in their own right, but they could be major new resources for people as well. Perhaps a plant as yet undiscovered will become an important food crop. There are probably many undiscovered plants that produce useful drugs to cure or treat human diseases. Biological diversity also provides an important source of new genes to improve the plants we now use. As techniques of genetic engineering improve, so will our ability to improve our domestic plants.