196 GARDEN GUIDE 



Most of the substances used against diseases contain sulphur or 

 copper. For diseases on surface, appearing like very fine dust, the best 

 substance to apply is flowers of sulphur. For other sorts of troubles 

 sprays seem better, since they can be distributed more evenly. Bor- 

 deaux mixture is the standard substance to use upon perennials just as 

 they come up in the Spring, but as it discolors the foliage, ammoniacal 

 copper carbonate and other substances are used when the plants are 

 in more advanced growth. 



Most diseases must be sprayed several times, otherwise the treat- 

 ment will be ineffective. 



The matter of strict sanitation cannot be too often emphasized. 

 To be specific, be sure that mummy fruits do not hang on the trees or 

 lie on the ground; gather all such disease breeding nuisances and put 

 them far away from the fruit trees. Certain of the weeds harbor 

 diseases which are common upon the cultivated plants; such weeds as 

 Mallow should be destroyed, because they harbor Hollyhock rust. 



