As biologists have learned more about the physiology of plants, the biochemical reactions involved in their growth, maintenance, and reproduction, and in their genetic composition, it has proved necessary to rename the science of botany. The study of plants is no longer a single discipline, but a group of related disciplines that are known collectively as the plant sciences. Scholars have been studying plants for thousands of years, and they have found, as researchers in every other area of science have found, that the more they learn the more unanswered questions they discover. Science is a never-ending process.

This short book has traced the history of plant science and plant use. It has described the medicinal uses of plants and how their cultivation led to the invention of gardens. It has outlined the development of written descriptions and catalogs of plants, which revealed a need for a system of plant classification that all naturalists could accept and use. As explorers visited distant lands they discovered plants that were unknown back home, and plant hunters traveled the world in search of species that could be cultivated for ornament or use. The book has told of the origins of plant cultivation, the unraveling of plant evolution, and the emergence of plant ecology.

The skills of plant scientists are needed now as never before. Unless food production increases rapidly, the predicted rise in the world population means there could be serious shortages by the middle of the 21st century. Plant scientists will need to develop new crop varieties that yield more, make more economical use of water, and are more nutritious than those being grown today. They will have to employ traditional breeding techniques and genetic modification—not least to minimize dependence on costly agricultural chemicals. Plant scientists also have another task, to identify, classify, and record the plant species that are growing in areas threatened by agricultural, forestry, or urban expansion. Without this knowledge it will be impossible to assess the extent of biodiversity and the risks to it. Among the previously unknown plants, there may be some that have the potential to become important sources of food, fiber, or drugs. There is no shortage of urgent tasks facing plant scientists. Perhaps, having read this book, you would like to become one of them and contribute to the important and exciting discoveries that will certainly emerge in years to come.