CONTENTS. 



Page. 



Introduction 



Historical notes 



Distribution and importance of crown-gall 9 



Geographical distribution of the disease - - 9 



Distribution of the disease on species and varieties of gra pes 10 



Distribution of the disease on young and old vines 10 



Importance of the disease 10 



Description of the forms of crown-gall 11 



Root galls n 



Cane galls H 



Other manifestations of the disease 12 



Development of the forms of crown-gall - 12 



Development of root galls 12 



Development of cane galls 13 



Development of the disease on seedlings 14 



Development of the disease in vineyards 14 



The effect of crown-gall 14 



The susceptibility and resistance of species and varieties of grapes to crown-gall . 15 



The susceptibility of varieties of European grapes 16 



The resistance of varieties of American grapes 18 



The cause of crown-gall 20 



The communicability of crown-gall 22 



Observations by other investigators 22 



Results of experiments 22 



Experiments with seedlings ' 22 



Experiments with older vines 24 



The cure of crown-gall 25 



Negative results from experiments with fungicides 25 



The prevention of crown-gall 26 



Resistant vines should be planted on their own roots 26 



Resistant stocks should be used for grafting nonresistant varieties 27 



Other means of prevention 27 



Summary and recommendations 28 



Index to literature 31 



Description of plates - 36 



Index 37 



183 5 



