CONTENTS 



PAGE 



History 3 



Present investigations 8 



Description of the nurseries 8 



Prevalence of the disease 9 



Etiology 11 



Isolation of organisms from diseased seedlings 11 



Inoculation and reisolation studies 15 



Comparative study of some strains of Rhizoctonia 17 



Cross-inoculation tests 19 



Cultural studies 22 



Conclusions from the cross-inoculation and cultural studies 25 



Control 25 



Application of muck 25 



Fall seeding. . . .' 26 



Soil treatments with chemicals 27 



Materials 30 



Methods of taking and interpreting data 32 



Results of the soil-treatment experiments 33 



Red pine — Liquid treatments 33 



Red pine — Treatments with dry chemicals 37 



Norway spruce — Liquid treatments 42 



Norway spruce — Treatments with dry chemicals 46 



White pine — Liquid treatments 49 



White pine — Treatments with dry chemicals 53 



Miscellaneous species 54 



Effect of the treatments on germination and subsequent growth of the 



seedlings. ..'...., 54 



Weed control 55 



Relative cost of different treatments 55 



General discussion and conclusions 57 



Summary 59 



References cited 61 



