CONTENTS. 



Page. 



Introduction 7 



Method of conducting the experiments 8 



Early experiments in corn cultivation 10 



Experiments in Utah 11 



Experiments of the Bureau of Plant Industry 12 



Resume of the corn-cultivation experiments 24 



Geographical distribution of the experiments 24 



Relative maturity of cultivated and uncultivated corn 25 



Relation of corn-tillage results to rainfall 26 



Relation of corn- tillage results to soil productivity 27 



Simplification of weed control where the soil is not stirred 28 



Fairness of the tests 30 



Relation of tests shown by frequency curve 31 



Interpretation of the results obtained 31 



Practical significance of the results 32 



Summary 34 



257 5 



