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(Colletotrichum ), leaf blight (Septoria), leaf blight (Cylindro- 

 sporium ) , leaf mold ( Alternaria ) , bacterial blight, downy mildew 

 ( Phytophthora ) and timber rot ( Sclerotinia ). The first six 

 occur to a greater or less extent in Massachusetts, some of them 

 occasionally causing considerable damage. The others have been 

 noted elsewhere and have often proved troublesome. 



For the present, spraying must be recommended for the treat- 

 ment of outdoor tomato diseases, although in some cases it is of 

 doubtful value, and the returns from the crop during certain 

 seasons in some sections would warrant little expenditure in this 

 direction. Proper training and pruning are beneficial and a 

 sufiicient ^vater supply is of value in the control of the blossom 

 end rot. 



The principal diseases afifecting greenhouse tomatoes are the 

 blossom end rot, timber rot, scab ( Cladosporium), eel worms, 

 wilt, surface molds, burn or scald, hollow stem. Oedema and 

 mosaic disease. Of these, the first four are the most important 

 and can be absolutely controlled, — the blossom end rot by sub- 

 irrigation, timber rot and eel worms by sterilizing the soil, and 

 scab or Cladosporium by regulating the air moisture. The re- 

 maining ones are of little importance and as a rule result from 

 abnormal conditions which should not be present. 



The most important features in greenhouse culture are those 

 connected with the management of the crop. Too great stress 

 cannot be laid upon the necessity of the gardener's understanding 

 the infiuence of such factors as heat, light, moisture, ventlation, 

 etc. He should be careful about introducing radical changes in 

 the management of the crop, and much discretion must be used 

 in the application of fertilizers. 



