^Ew York Agricultural ExPERniEXT Station. 203 



SUMMARY FOR ORCHARD V. 



Although twenty infested trees were used in these experi- 

 ments and unusual pains taken to make the applications thor- 

 ough there were no beneficial effects apparent in either case. 

 The scales were breeding as rapidly during the summer on the 

 treated trees as on the checks. Although there was a week 

 of dry weather immediately following the applications, the un- 

 favorable results may have been due in large part to an unusu- 

 ally wet spring. The heavy rains washed both compounds 

 almost entirely off before the summer was over. Further experi- 

 ments with these washes seem desirable as they have not yet 

 been sufficiently tested to prove or disprove their value. 



GENERAL SUMMARY. 



The experiments with crude petroleum include 321 fruit trees 

 consisting of apples, cherries, pears, peaches and plums. The 

 results were fairly uniform. In the experiments of Series I no 

 injury was caused by the 25 per ct. emulsion, but in every case 

 the 40 and higher percentages caused serious injury to the plum 

 trees while the pear and cherry trees were practically un- 

 harmed. The younger and more vigorous plum trees were 

 injured less than the old and weaker ones. 



The experiments included in Series II show serious injury to 

 peach trees by the 25 per ct. emulsion and equally serious 

 injury to plum and apple trees by the 40 per ct. emulsion. In 

 all cases of injury it is to be noted that the most serious injury 

 was caused by the fall applications and by two applications- 

 one in the fall and one in the spring. These results do not agree 

 with those of Smith and Corbett previously referred to but agree 

 in the main with those of Felt who, as previously stated, found 

 that the undiluted petroleum caused serious injury to the 

 treated trees. 



The experiments to ascertain the percentage of petroleum in 

 the petroleum and water emulsion required to kill the hibernat- 

 ing scales also gave uniform results. The 25 per ct. emulsion 

 failed to affect the scales materially while the 40 per ct. killed 



