EXPERIMENT STATION BULLETINS. 297 



SPRAYING THE ORCHARDS. 



While it is impossible to give any very definite directions for the spray- 

 ing of fruit trees, owing to the differences that will always occur, from 

 tlie nature of the varieties, the character of the season as well as the 

 efifect of the soil and location, a few general directions for the spraying 

 of orchard trees may be helpful. For the most part the fliaterials will 

 be the same for all classes of fruits, so far as the ordinary sprayings 

 are concerned, and they should be applied at practically the same peri- 

 ods. It will, of course, occasionally happen that some of the fruits are 

 attacked by insects that are not found upon other species and addi- 

 tional remedies will be required. Some slight modifications of the di- 

 rections will be necessary to adapt them to local conditions, as. while 

 two or three sprayings in a season may be suflScient in some cases, five 

 to seven may frequently be made with profit in others. 



THE APPLE ORCHARD. 



To protect the foliage and fruit of apple trees from the attack of 

 dangerous insects and diseases it is important that they be kept cov- 

 ered during the periods these insects and diseases are most likely to be 

 troublesome, w^ith such materials as will make it impossible for them 

 to injure the trees. The disease that is most common upon apple trees 

 is known as apple scab. This is a fungous disease which in some cases 

 entirely ruins the crop and can be held in check by Bordeaux mixture. 

 For the earlier applications use three or four pounds of copper sulphate 

 and five or six pounds of lime to fifty gallons of water. Later, this can 

 be reduced to two or three pounds of copper sulphate and three or four 

 pounds of lime in the same amount of water. The foliage of apple trees 

 is often destroyed by insects, caterpillars, canker worms and other leaf- 

 eating insects, while the fruit is attacked by curculio and codling moth. 

 For these and other chewing insects an arsenite, such as Paris green, can 

 be used with good results at the rate of one pound in every seventy-five 

 to one hundred fifty gallons of water, or better yet with Bordeaux 

 mixture. This insecticide sometimes burns the foliage and it is also 

 readily washed from the trees. The former can be, to a large extent, 

 prevented by the addition of two pounds of lime for each pound of Paris 

 green, or by applying it in Bordeaux mixture which contains an excess 

 of lime. Another remedy which is preferred to Paris green from the 

 fact that it does not burn the foliage and because it has superior ad- 

 hesive qualities is arsenate of lead. This is generally used at the rate of 

 two to three pounds in fifty gallons of water. Its one drawback is the 

 high cost, which is about fifteen cents per pound or about four times as 

 much as Paris green for the fifty gallons. While its use might not be 

 warranted for the entire season, it will ordinarily be worth while to 

 apply arsenate of lead for the last spraying in June and for the one given 

 the second brood of codling moths in August. The above remedies 

 38 



