972 NEW YORK STATE MUSEUM 



May 14. Tree 20 has only a few tips and the suckers starting. Its 

 condition at this time is represented on pi. 6. Tree 21 . The tips of most 

 of the branches bear only a few leaves. There are very few blossoms. 

 Tree 107. The leaves are starting on only a few twigs and suckers. 



May 28. Tree 20, Only four small twigs in the top have developed 

 leaves, and these are small. The foliage of the suckers is vigorous, 

 though light. Tree 21. The leaves are rather abundant for a tree treated 

 with kerosene. The top of tree 107 is nearly dead. The foliage of the 

 suckers is rather vigorous. 



June 20, There are only a few leaves in the top of tree 20. The 

 suckers were trimmed down to one. The leaves out pretty well on some 

 branches and a number of others are dead. Suckers are being thrown 

 out, and the tree may eventually recover. The top of tree 107 died 

 and was cut off. 



July 2. There are apparently no living scales on trees 20 and 107; on 

 tree 21 they are rather abundant. For c ondition of tree 21 at this time 

 see pi. 4. 



Aug. 3. There are apparently no living young on tree 20, and but a 

 few on tree 21. Many living young are found on tree 107. 



Sep. 7. The top of tree 20 is dead and the suckers are growing rather 

 vigorously. Young are abundant on tree 21. Tree 107 was cut back, 

 and only the stump remains. 



Oct. 25. Even the suckers of tree 20 are in bad condition and 

 appear to be dying back. There are many suckers on tree 21, and con- 

 siderable scale, but it is not in very bad condition. 



Experiments with crude petroleum against San Jose scale. 



Considerable has been said in recent months about the value of crude 

 petroleum, and one entomologist has stated, in giving his conclusions 

 regarding its effects on fruit trees, that this substance " is harmless to the 

 most tender varieties and on the youngest trees." This opinion has since 

 been modified, it is only fair to state. Crude petroleum is undoubtedly 

 a valuable insecticide when its use is understood, and when a product 

 with a definite composition can be secured. Very diverse results have 

 been obtained by experimenters with this material, and some of them, 

 at least, can undoubtedly be charged to the difference in composition of 

 the petroleum. Crude petroleum, as now placed on the market, is a 

 mixture of the product of a number of wells, the proportion of oil from 

 each varying with the productivity of the well and influencing the com- 

 position of the whole to some extent, at least. The oil used in the 



