The Indiana Weed Book

PREFACE. EVERYONE cultivates the soil, whether on the farm or garden, is perforce interested in weeds, for their absence or presence amongst the crops has much to do in determining the relative success or failure of the undertaking. A very great deal has been written on the subject, but the information is widely scattered throughout the literature of agriculture and botany. In this country, at least, very few efforts have hitherto been made to gather up and correlate this varied knowledge, thus rendering it accessible to those most interested. Furthermore, it is only of recent years that definite attempts have been made to work out the quantitative and qualitative relations between weeds, the soils on which they grow and the crops with which they are associated. In this respect the c, onclusions so far drawn can only be regarded as tentative subject to modification and revision as more data become available. It has seemed justifiable, therefore, to attempt to set forth the present position of affairs, in order that future attacks on the weed problem may be more co-ordinated, and that valuable time and labour may be utilised to the best advantage. The original investigations embodied in the following pages owe much to the cordial assistance afforded by the many landowners and farmers whose land has been utilised for the purpose. It is impossible torecord each individually, but my special thanks are due to Professor T. B. Wood, Mr. Spencer Pickering, Mr. E. S. Beaven, Mr. E. E. Stokes, and Mr. J. H. Burton, all of whom facilitated the work by giving me introductions throughout the districts with which they were best acquainted. Miss M. B. Lee and Miss V. G. Jackson have rendered valuableassistance with the proof sheets, and, above all, I am specially indebted to Dr. E. J. Russell for his constant advice and criticism throughout the preparation of the book. W. E. B. ROTHAMSTED, June, 1920. CONTENTS. PAGE CHAPTER I. - - - - - - - - - - - INTRODUCTION-I CHAPTER 11. DISTRIBUTIONOFWEEDS - - - - - - - - - 10 CHAPTER 111. PREVENTIO A N N D ERADICATIO OF N WEEDS - - CHAPTER IV. VITALITYOFWEEDSEED - S - - - - - - - - 72 CHAPTER V. - - - - - - - - - - HABITSOFWEEDS-84 CHAPTER VI. CHAPTER VII. - POISONOU A S ND INJURIOUWSE EDS - - - - - - - - 103 CHAPTER VIII. ARABLEW EEDS. ASSOCIATIO W N IT H SOILS. I. GENERAL - - - 117 CHAPTER IX. ARABLEW EEDS. ASSOCIATIO W N IT H SOILS. 11. SPECIAL - - - 121 vii CONTENTS PAGE CHAPTER X. ARABLWE EEDS. ASSOCIATI W O I N TH CROPS - - - - - - I59 CHAPTER XI. GRASSLANWDE EDS - - - - - - - - - - 175 CHAPTER XII. USESOPWEEDS - - - - - - - - - - - 187 CHAPTER XIII. POPULA A R N D LOCALN AMES O F WEEDS - - - - - 206 LIST OF ILLUSTRATIONS. FIG. 31. RED BARTSIA B artsia odontites, parasitic on Wheat - Frontispiece 4. SPIKELET O F FRUITS O F WILDO AT Avenaf atua - - - - 16 5. KNOTGRAS P S o lygonum aviculare - - - - - - - 19 6. FRUIT O F NARROW-LEAVVEEDT CH Vicia angustifolia - - - 21 7. A. WINGED SEED OF YELLOW RATTLE Rhinanthus crista-galli - 22 B. WINGEDS EED OF SPURRY S pergula arvensis - - - C. WINGEDF RUIT O F HOGWEED N eracleum sphondylium - D. WINGEDF RUIT OF BROAD-LEAVEDDO CK Rumex obtusifolius 8. PLUMEDF RUITS A. Coltsfoot Tussilago farfara - - - - - - B. Creeping Thistle Cirsium avvense - - - - - C. Hawkbit - - - - Leontodonhispidus-D. Dandelion Taraxacum vulgare - - - - - E. Groundsel Senecio vulgaris - - - - - - F. Goatsbeard Tragapogonpratensis - - - - - g. PLUMEDS EEDS O F WILLOW-HER B E pilobium sp. - - - 10...