268 THE MONTHLY BULLETIN. 



to say more and would not except that such colossal losses are being 

 sustained by such a large number of the fruit growers, that so many are 

 passive in an effort to control the pest and the further fact that the 

 disease can be controlled. Entire pear orchards and orchards of whole 

 communities have been known to be blighted and die because of this 

 terrible pear blight. Other orchardists are seemingly indifferent or 

 are adopting measures entirely inadeciuate to cope with the disease. I 

 know of men who have been fighting the plague persistently for three 

 years, never flagging in winter or summer for even a day, and who 

 have had bumper crops each season. These men have proved that 

 success is possible, and their immense and phenonu^nal profits ought to 

 make their example contagious. We now know positively that this dis- 

 ease is caused by a specific germ and that the germ is in the sap at 

 disease locations. We also know that birds, insects, anything that 

 pierces the diseased wood and then passes to healthy wood to penetrate 

 the bark and cambium on the same and other trees, will spread the 

 blight. 



Bees have been accused as the major agents of bliuht dispersion. 

 It is probable that other insects, especially aphids (plant lice) are (piite 

 as active in this fell destruction. It is thought that the utter seclusion 

 of bees from the orchard will not reduce pear blight appreciably. We 

 know that the disease lurks in blossoms, fruit, twigs, branches and 

 roots. Wherever in any of these locations infested sap is conveyed, 

 there the disease will very likely show its deadly presence. 



It has been fully demonstrated that cutting out — absolute extirpation 

 — is the only effective cure, but this disease is so insidious that many 

 people will fail to do the proper cutting. Roots, trunks, branches, twigs, 

 all must be gouged to ascertain if the infection is present, and when 

 discovered everv last atom of diseased tissue must be cut away. Whole 

 roots may be diseased and must be excised. The bark, cambium and 

 outer sapwood may be harboring the fatal germs and they also must be 

 cut away. In some cases the disease seems to penetrate deeper than 

 has hitherto been supposed in the sapwood. To show how exacting 

 this requirement is, I have but to say that I know of a case where a 

 very active, experienced man worked three days on a single tree cutting 

 away infested portions, yet the owner who has fought pear blicrht ten 

 years set Qut a large area to pears the past season. Figure 59 shows 

 something of the difficulties of this work of eradication. It is interest- 

 ing to know that this tree has borne great crops of pears each season 

 and as will be seen, is loaded with healthy bloom at the present time. 



It is also imperative in fighting pear blight that the cutting instru- 

 ment shall be disinfected after each cutting. Nfiwr cut a ftrco)ul li)i}e 

 Kiilil the ijistntment is disinfected. Without doubt corrosive sublimate, 

 bichloride of mercury, is decidedly the best disinfectant. Of course this 

 will appear to be a great task, but pear blight is so common and orchard 

 destruction so general that it is believed it will more than pay to take 

 all possil)le ])ains to destroy tlicsi^ fatal germs. In no way can the 

 county horticultural commissioner do more good in Ihe case of pear 

 blight infesting the orchards of his county than to demonstrate to the 

 growers the fact of control and to insist that eradication be general and 

 complete. — A. J. C. 



