764 NEW YORK STATE MUSEUM 



There is a brief mention of the occurrence of the little black 

 ladybug, Pentilia misella Lee, in my previous report, 1 

 but this year it was observed in much larger numbers on infested 

 trees in the experimental orchard and also in an infested 

 orchard near by. It was much more abundant in the latter, 

 probably on account of the much larger number of scale insects, 

 since practically nothing had been done to keep the pests in 

 check. This beneficial form was not present in sufficient num- 

 bers to attract notice till Sep. 25, and from then till the middle 

 of October, at least, the beetles were quite numerous; 50 on a 

 small badly infested tree would not be an excessive estimate. 

 These ladybugs, however, do not seem to have made much im- 

 pression as yet on the San Jose' scale; and, though they were 

 much more abundant in the adjacent orchard where no insecti- 

 cides of any account had been applied, the scale had not been 

 affected enough to warrant a hope that eventually this pest 

 may be controlled by this little natural enemy. It certainly 

 would not be wise at present to defer treatment with insecti- 

 cides on account of the presence of this tiny ladybug. 



The fruit tree bark beetle, Scolytus rugulosus Ratz., 

 also occurs in the experimental orchard, attacking a number of 

 trees last year but injuring only one very seriously. This was 

 broken down by wind or other agency, and the beetles entered 

 the prostrate limbs in large numbers. This year a light oxheart 

 cherry (tree 4) was attacked by this beetle and injured consid- 

 erably. It was in excellent condition last year, but toward the 

 end of the season became rather badly infested with San Jose* 

 scale. July 3 it was found to be infested with Scolytus. 

 There was a copious exudation of sap or gum and a number of 

 edematous swellings were observed here and there. The tree 

 was quite badly affected Aug. 9. Several other trees were at- 

 tacked to a less extent by this borer. 



Appearance of oil on trees. This general note applies to all 

 trees treated with crude petroleum or mechanical emulsions of 

 the same. May 22, the oil shows very plainly, and all of the 



1 N. Y. state ent. 16th rep't. 1901. p. 970. 



