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8th. Repeat the copper acetate after a week or ten days. 



The total cost of this treatment is estimated by Professor 

 Chester at twelve cents per tree where everything is done 

 economically, and in the experiments reported about three- 

 fourths of the rot was prevented. He admits some 

 dropping of the leaves as a result of the spraying, but 

 thinks this injury more than balanced by the foliage hang- 

 ing much later in the fall on the treated than on the un- 

 treated trees. 



Leaf Rust.— This is caused by a fuugus {Puccinia 

 pruni-spmosae) closely related to the rusts of grain. It 

 often develops abundantly on peach and plum leaves late in 

 summer, causing them to fall prematurely. This and other 

 leaf destroying fungi will probably be effectively controlled 

 by the spraying suggested for the rot. 



GuMMOSis. — This is an obscure diseased condition that 

 manifests itself by the occurrence of blisters or pockets 

 filled with gum under the bark of the trunk and branches. 

 It is not to be confounded with the copious flow of gum 

 occasioned by injuries from borers or other mechanical 

 causes. It is accompanied by a serious constitutional de- 

 rangement of the tree, and frequently causes its death, 

 but the nature of the disease is not known, and no remedy 

 can be suggested. 



APPLES, PEARS AND QUINCES. 



These pomaceous fruits are subject to many of the same 

 diseases, the most important of which is the — 



Blight. — This is a bacterial disease caused by the 

 growth of a minute germ or microbe in the young, soft 

 tissues of the tree. The diseased parts soon die, and the 

 blackened persistent leaves can be seen hanging as a signal 

 of distress in most Southern orchards. As the wood 

 growth begins to harden, the disease becomes less active 

 and usually dies out of its own accord. In such cases a 

 distinct riug marks the union of the dead and living bark. 

 In a few cases, however, the disease does not stop, but 



