REPORT OP THE STATE ENTOMOLOGIST 1903 153 



young which had evidently developed within the last two or three 

 weeks. 



The ultimate effect of successive applications of crude petro- 

 leum to various fruit trees is of some interest, and on this account 

 we purposely made annual applications to certain trees, and an 

 examination of them is not without interest, since while it shows 

 some injury, the damage is not so serious as it first appeared. 

 For example, tree 101, a seckel pear, was very badly infested in 

 1900, when it was sprayed with undiluted petroleum and seriously 

 injured. The following year it was treated with a mechanical 

 mixture consisting of 15$ oil and a whale oil soap solution, 1 

 pound to 4 gallons, and in the spring of 1902 and of 1903, with 

 20$ mechanical emulsion. The tree at the outset, as above noted, 

 was in poor condition. It has been steadily improving, and last 

 December had developed a large amount of new wood, and during 

 the present season has made a fair growth, though the foliage is 

 rather light in color and less than normal size. Tree 114, a pear 

 of the same variety, received undiluted crude petroleum in 1900, 

 but was not injured so seriously as 101. Each subsequent year it 

 has been sprayed with a mechanical crude petroleum emulsion and 

 is now in a vigorous condition and in much better state than three 

 years ago, though the roughness of the bark on the trunk is becom- 

 ing more pronounced. Tree 69, a Howell pear, was sprayed in 

 1900 with the whale oil soap and petroleum combination, and with 

 mechanical petroleum emulsions the three succeeding springs, and 

 is now in as good condition as others which have not been sub- 

 jected to annual applications of oil. The same is practically 

 true of tree 66, a Bartlett pear. Other instances might be cited, 

 but enough has been given to show that ordinary fruit trees can 

 stand at least four applications in successive years with- 

 out much injury. The benefits resulting from this treatment 

 in the vicinity of Albany, as compared with those accruing from 

 the lime-sulfur combinations, were so marked that the owner has 

 repeatedly urged us to apply the oil to the entire orchard, because 

 the lime-sulfur wash had not proved satisfactory in controlling 

 the scale. It is only fair to add that much better results have 



