FIFTY-FIRST ANNUAL REPORT. 49 



The next point of importance to be observed is tlic condition of the soil> 

 namely the soil temperature and the soil moisture. The temperature 

 of the soil should be 55 to 60°F to a depth of 4 inches. This condition 

 exists in Michigan between the last of May and the last of September. 

 If lower temperatufes are had, the gas does not evaporate as (piickly 

 and the oxygen requirement of the borers is less, consequently a longer 

 exposure to kill them is necessary, and this may be injurious to the 

 tree. 



The amount of moisture in the soil at the time of making the appli- 

 cation should be very slight, in fact, a dr}' or semi-dry soil is desired. 

 If the soil is wet, the air spaces between the soil particles are filled with 

 water, consequently the gas cannot penetrate the soil, and the gas is 

 highly insoluble in water. A wet soil tends to be cold and this slows up 

 the evaporation, so that a longer exposure is necessarj\ 



The time of application is another essential point and it should be 

 from August 25th to September 10th. The temperature then ranges 

 from 55 to 60°F and even higher. An application at this time of the 

 year gives ample time for the crystals and. gas to get out of the soil before 

 freezing weather. This treatment also prevents further infestation in 

 the fall and keeps the trees from borers during the winter, the following 

 spring, and the early summer months. One application seems to be 

 sufiicient, although in very bad cases, it ma}^ be advisable to make two 

 treatments with short exposures, — one in June and the other in August. 

 Early spring treatment is not advised, since the soil is too cold and 

 wet. 



Paradichlorobenzine may be obtained from the following companies: 

 The Dow Chemical Co., Midland, Michigan; Niagara Sprayer Co., 

 Middleport, N. Y. ; and the Hooker Electro-Chemical Co., 25 Pine St., 

 New York City. The price ranges from 15c to 30c per pound, and the 

 cost of making the application, including labor, ranges between 3c and 

 4c per tree. 



In six counties, — Calhoun, Berrien, Kalamazoo, Van Buren, McComb, 

 and Cass,— 940 trees were treated and the treatment was highly success- 

 ful. That should be sufficient evidence for the most skeptical grower, 

 but for those that are still in doubt, it is recommended that they try 

 the treatment on a small block of trees. When you stop to think of the 

 ease with which this treatment is given, in comparison with the digging 

 out of the bores by hand, there should not be a doubt as to which of 

 the two methods is the best, the least injurious to the trees, and the 

 more pleasant. 



THE OUTLOOK FOR PEACHES IN MICHIGAN. 



G. G. GEISLER, HARTFORD, MICHIGAN. 



Peach growing is an important industry in Michigan, especially in 

 the western part and centering around the southwestern section. The 

 peach industry of recent years reached its climax about 1916, the crop 

 of 1917 being almost a total failure. Many of the orchards were killed 

 in the winter of 1917-18. About 50% of the trees were killed outright 

 and the remaining 50% were damaged to such an extent that the pro- 

 ducing power was decreased to about 25 or 30% of what it was before the 

 freeze. 



