Nature is the great farmer. Continually she sows and reaps, making all the forces of the universe her tools and helpers. The sun's rays, wind, rain, frost and snow, insects and birds, animals small and great, even to the humble burrowing worms of the earth, all work mightily for her and a harvest of some kind is absolutely sure. And to the people who must wrest a living from the soil, not only for themselves but for all mankind besides, it must seem that Nature's favorites are the hardy, aggressive, and often useless and harmful plants which they have named weeds.

Yet, when man interferes with the Great Mother's plans and insists that the crops shall be only such as may benefit and enrich himself, she seems to yield a willing obedience, and under his guidance does immensely better work than when uncontrolled. But Dame Nature is an "eye-servant"; only by the sternest determination and the most unrelaxing vigilance can her fellow-worker subdue the earth to his will and fulfill the destiny foreshadowed in that primal blessing, so sadly disguised and misnamed, when the first man was told, "Cursed is the ground for thy sake; in sorrow shalt thou eat of it all the days of thy life; thorns also and thistles shall it bring forth to thee; and thou shalt eat of the herb of the field." A stern decree. But the civilization of the peoples of the earth is measured by the forward state of their agriculture; and agriculture in its simplest terms is the compelling of the soil to yield only such products as shall conduce to the welfare of the people who live upon it. It resolves itself into a contest with nature as to what plants shall be permitted to grow, and the discovery of the easiest, surest, and most economical means of securing a victory in the strife.

In agriculture, as in every field of labor, modern invention and discovery have greatly multiplied the power and efficiency of each pair of human hands; but still in this contest with nature and the growing plants, it frequently happens that those hands are the only tools which can be used effectively - as the writer knows by many years of hard practical experience, both in garden and in field. Again, some simple expedient of little cost and easy application, may do the work of many hands and increase by many fold the soil's return for the labor. A wider acquaintance with such methods of control seems desirable and therefore the writer has endeavored to bring together, so far as could be learned, the knowledge gained by much study and careful experiment in many different parts of the country by earnest and thoughtful workers. There is a great dearth of books on this most important subject, but such as could be obtained have been diligently studied. The Bibliography on page 559 will indicate the writer's debt in this regard. Many files of agricultural periodicals have been consulted and most grateful acknowledgment is made for assistance received from the publications of the Department of Agriculture at Washington, and to the Agricultural Experiment Station Bulletins of the various states and of the Canadian Provinces.

In nomenclature and order of classification the writer has followed Gray's New Manual of Botany, seventh edition, 1908. For plants outside of the geographic limits included in that book, Coulter and Nelson's New Manual of Rocky Mountain Botany, and W. L. Jepson's Flora of Western Middle California, have been consulted. For range, season of bloom and fruit, and much other very important and necessary information, most invaluable help has been obtained from the New Illustrated Flora of the Northern United States and Canada, by Britton and Brown, and the revised Flora of the Southeastern United States, by Dr. J. K. Small. Statements concerning plants that are poisonous or otherwise harmful to health have been made on authority of publications issued by the United States Department of Agriculture. Dr. L. H. Pammel's Manual of Poisonous Plants has also been a helpful reference. Mention is made of the fact that some weeds are medicinally valuable, and may occasionally be made to pay for the cost of their extermination. The writer's authority for prices and modes of preparation has been the interesting series of bulletins prepared by Miss Alice Henkel, Assistant, Drug-Plant Investigations, at the Bureau of Plant Industry at Washington.

The writer desires to express most grateful acknowledgment to Professor James G. Needham for helpful suggestions as to the plan of the book and reading of the manuscript; to Professor Karl M. Wiegand for reading, criticism, and amendment of the text while in proof; and to Miss Lela A. Gross of the Editorial Department of the New York State Agricultural College for reading the proof.

The writer has attempted - not very successfully - to make the terms of the descriptive text somewhat less technical and easier for the general reader to understand than that of the botanies; but one who makes even a modest effort in that direction soon realizes the difficulties, for, after all, technical terms are exact, and no paraphrase, however carefully defined, can be made so fit. "Seeds" are often mentioned by that term, because it is the only one used by the seed merchant and the farmer, to whom, also, any capsular fruit is likely to be a "pod." Of the common names given, the writer has in every case selected for a heading the one considered to be in widest and most common use for the plant described.

A few paragraphs of the introductory chapters are rearranged from some lessons about weeds which were furnished by the writer for the Leaflets of the Home Nature-Study Course, while serving as Assistant in the Bureau of Nature-Study at Cornell University. These leaflets, however, are now out of print. To make a book that would be helpful to any one who loves and grows plants, and must combat weeds in order to help them to grow, has been for many years the writer's strongest wish. In the hope that it may be one of the few wishes that "come true," this book is given to the public.

Ada E. Georgia.

Ithaca, New York, July, 1914.