CONTENTS 



PAGE 



Introduction ............ 1 



Wildfire in the Connecticut Valley ....... 1 



Wildfire in other sections ......... 2 



Progress in investigations ........ 2 



Life history studies .......... 3 



Overwintering of the bacteria ........ .3 



Effect of freezing the bacteria ....... 3 



On the seed .......... 4 



In the soil .......... 5 



In cured leaves .......... 7 



In leaves which have been left in the field ..... 8 



Occurrence of lesions on stalks ........ 8 



Occurrence of lesions on midribs ....... 9 



Relation of the condition of the plant to infection .... 9 



Dissemination .......... 10 



Control measures . . . . . . . . . . .11 



Sterilization of seed . . . . . . . . . .11 



Sterilization of soil in the seed-bed ....... 13 



Sterilization of sash and plank . . . . . . . .14 



Spraying and dusting seed-beds ....... 15 



Conclusions from the experiments and practical applications . . 16 



Frequency of application ....... IG 



Amount of material to be applied ...... 17 



Relative cost of dusting and spraying ..... 17 



Dust V. liquid sprays ......;. 18 



Home-made v. commercial copper sprays . . . .18 



Best time of day for application ...... 18 



Absolute V. partial elimination of wildfire . . . .18 



Will clean beds, give clean fields ...... 19 



Success by practical growers ...... 19 



Value of an arsenical in the fungicide ..... 19 



Dust burn and spray injury ....... 19 



Secondary benefits ........ 20 



Conclusion ......... 20 



Destroying diseased areas in the bed ....... 20 



Removing all plants from a diseased field and resetting with healthy 



plants 21 



Roguing without resetting ........ 22 



Picking ofi' diseased leaves ........ 22 



Dusting the plants in the field ........ 23 



Spraying with Bordeaux mixture in the field ..... 24 



The outlook for 1923 25 



Condensed recommendations for control ....... 26 



Publications on wildfire cited in this bulletin ...... 27 



