BLIGHT IN THE APPLE ORCHARD. Ig7 



very improbable from what is known of its organism that it is ever 

 carried by the wind. 



Blight is native to the Unites States and hibernates during; 

 winter in diseased portions of apple wood, usually at the base of 

 some of the blighted branches. During warm days in spring this 

 blight may be seen oozing out of diseased apple wood, forming a 

 thin, sticky substance that is fed upon by insects and by thern is 

 carried to the bloom of our apple trees, where it increases in the 

 nectar of the blossom with wonderful rapidity. From there it is 

 carried by the busy little bee and other insects to healthy blossoms, 

 which in turn become diseased. This is how we get that form 

 known as "blossom blight." Later in the season we get another form 

 of this same disease — we sometimes call it "fire blight." 



It makes no difference what slope the orchard is upon, if at this 

 time the blight is very bad it is almost certain that the trees are 

 making a too rapid growth ; there may have been too much manure 

 and cultivation, a succession of rainy and hot days, and probably 

 general hothouse conditions prevail in the orchard. 



Here again is where the insect gets in its work. Much of the 

 blight-poisoned sap oozes from diseased wood, and some of it may 

 be carried on the feet of insects to healthy wood. The germs 

 rapidlv find entrance through the expanding bark of the new and 

 succulent growth and are carried downward by the circulation of 

 the sap, which emits a poisonous substance that destroys tlic tis- 

 sues of the wood in which they work. 



When cooler and dryer weather prevails the blight often sudden- 

 Iv ceases, the slower growth of the trees causing a slight thickening 

 of the sap and a firmer condition of bark. Blight spreads rapidly 

 onlv when the sap is very thin and watery and the circulation rapid. 



Now for some of the sanitary measures for the purpose of re- 

 ducing the blight : if in the bearing orchard reduce the cultivation 

 or cut it out altogether ; if the orchard is in sod, and tlie plow must 

 be used, let it be done in autumn but never after active growth has 

 begun. Anyway, I believe, cultivation should not be extended be- 

 yond the 15th of June. 



We cannot control the elements, nor can we prevent a suc- 

 cession of rainy nights and hot, sunny days, neither can we get en- 



