174 EXPERIMENT STATION. [Jan. 



thicker tliaii at the opposite side of the twig, where the tension is 

 different. 



Microscopical examinations of sections also showed that con- 

 siderable healing of the wound caused by gummosis took 

 place. The callus forming as a result of this healing developed 

 ridges along the side of the wound. The cavity of the wound 

 was entirely filled with gum, which contained Cladosporiuni 

 and a form of AUcrnaria. 



Suggestions in Begaid io tlie Treatment of Gummosis. 



In very l)ad cases of gunnnosis it would be best to destroy 

 the tree, since it is of little value and may possibly furnish 

 an ideal place for the development of undesirable organisms. 

 Eranches may be cut off a few inches below the affected areas. 

 Since this disease undoubtedly originates from the practice of 

 leaving " mummied " fruit attached to the tree, it is best to 

 remove and destroy them. It is even a question whether " mum- 

 mied " fruit should be left on the ground. Practically all cases 

 of infection from giimmosis have occurred where the " mum- 

 mied " fruit was left on the tree, and came in contact with the 

 limb or branch. 



Care should also be exercised in pruning, and this should be 

 done in winter or early spriug. A clean, sloping cut should be 

 made, and large wounds should be covered with paint or coal- 

 tar. This treatment will prevent infection from the wounds. 



The practice of good sanitation and systematic spraying of 

 peach trees, together with cultivation and feeding, will un- 

 doubtedly hold this disease in check. 



DlRECTlOA'S FOR MAKING SuMMER SPEAY MiXTURE. 



Essentials. 

 In making the self-boiled lime sul])hur, plus arsenate of lead. 

 as recommended for the summer sprayings, the first essentials 

 are to have good stone lime, a perfect mixture of the ingredi- 

 ents, and tw^o men to attend to the mixing. After being mixed 

 it is necessary that the mixture l)e kept well agitated while in 

 the taid\, for if not it will settle, no matter how well made. To 



