134 NEW YORK STATE MUSEUM 



following trees, 18, 25, 36, 37, 38, 40, 41, 43, 47, 65, 79, 82, 83, 



84, 85, 105, 106, 108; young were rather abundant on trees 15, 16, 

 21, 22, 23, 28, 44, 61, 68, 69, 114 ; and young were very abundant on 

 tree 73. 



These trees were again carefully inspected Nov. 11 by my 

 assistant, Mr Walker, who rated them as follows. Condition 

 good, trees 15, 16, 17, 18, 19, 24, 25, 26, 27, 34, 35, 36, 37, 42, 43, 

 44, 45, 47, 60, 61, 62, 63, 64, 65, 66, 68, 71, 79, 80, 81, 82, 83, 84, 



85, 86, 87, 88, 89, 90, 91, 101, 102, 103, 104, 105, 106, 109, 110, 111, 

 112, 113, and 114. The following were classed as being in a bad 

 condition, that is having on them a number of living scale 

 insects, trees 21, 22, 23, 38, 40, 41, 69, 70, 108; and trees 28 and 

 73 were rated as being very bad. 



It will be seen by the above that onl}- two trees were in very 

 bad shape at the end of the season, and both of these were 

 badly infested when the spraying was done last spring. Many 

 of those classed as being in bad condition have the bark of the 

 larger limbs and trunk rongli, and this interferes materially 

 with the efficiency of the insecticide. A comparison of the con- 

 dition of these 70 trees with the 50 at the other end of the orchard 

 sprayed with lime, salt and sulfur mixture is quite marked 

 and emphatically in favor of treatment with the oil. It should 

 be stated however that the relative inefficiency of the lime, 

 salt and sulfur mixture was probably due to the rains following 

 so shortly after application and continuing so long [see page 

 132]. These had practically no effect on the oil and therefore 

 gave it the advantage. 



The writer at the outset raised the question as to the pos- 

 sibility of injury resulting to trees which had been sprayed 

 with petroleum for successive seasons, and now he is in a position 

 to supply a little data on this question. Trees 25-28, 41-47 and 

 101-14 have received applications of crude petroleum for three 

 successive seasons. Tree 101, a seckel pear, was very badly 

 infested in 1900 when it was sprayed with undiluted petroleum 

 and sustained serious injuries. The following year it was 

 sprayed with a mechanical mixture, consisting of 15;^ oil and a 

 whale oil soap solution, 1 pound to 4 gallons. Last spring it 

 was sprayed with the 20;^ mechanical emulsion. This tree was 

 in very bad condition at the outset, and, as above noted, was 



