590 THE MONTHLY BULLETIN. 



GENERAL NOTES. 



THE INTRODUCTION OF CALOSOMA FOR USE AGAINST 



THE OAK MOTH. 



During the past month the California oak moth, Phryganidia cali- 

 fornica, has been doing very serious damage to oak in this State and 

 especially in the Santa Clara Valley. Entire defoliation is a common 

 occurrence, and with the coming on of the second brood very serious 

 damage will probably be done, although this may be prevented by the 

 attack of the native parasites which are sometimes sufficient to hold it 

 in check. The recurrence of this moth every season has led us to 

 believe that an attempt to introduce Calosoma sycopJianta to prey on 

 this worm would be well worth while. Calosoma sycoplianta is a large 

 green beetle very similar in appearance to our Calosoma scrutator, but 

 is much more valuable for the reason that the larvae of this imported 

 beetle are more proficient in tree climbing. Calosoma sycoplianta has 

 been introduced by the U. S. Bureau of Entomology into New England 

 for use against the gypsy moth, and this introduction has been an 

 eminent success. It is probable that this beetle is, up to the present 

 time, the most efficient of all of the introduced enemies of the gypsy 

 moth. The credit for the successful outcome of the experiment in 

 New England is due to Mr. A. P. Burgess and it is through his kindness 

 and that of Dr. L. 0. Howard, Chief of the Bureau, that we are sup- 

 plied with a stock of these beetles for use in this State. 



The insect is a native of South Europe, being found commonly in 

 Southern France, Italy and Sardinia. While the gypsy moth is 

 probably the food most preferred by Calosoma sycoplianta, it also feeds 

 voraciously on many other varieties of caterpillars, and there is but 

 little doubt that it will find the California oak moth very much to its 

 liking. The fact that this moth is present through a rather long season, 

 it having more than one generation, and the similarity of our climate 

 to that of the native habitat of this beetle, leads us to hope that it will 

 thrive in California and become a valuable factor in the control of this 

 pest. As oak trees are difficult to spray and as the operation is very 

 expensive, we believe that this is one of the instances where no effort 

 to obtain control through natural enemies should be spared. Besides 

 the oak worm we have the fall-web worm, several species of tent cater- 

 pillars, several tussock moths, the canker worms and the red-humped 

 caterpillars, all of which should form food for this beetle. — Harry S. 

 Smith. 



ARSENATE OF LEAD VS. PARIS GREEN. 



For years, Paris green, and later London purple, were the almost 

 exclusive arsenical poisons used to combat mandibulate or biting insects. 

 Owing to the fact that the commercial acids were in part soluble they 

 often blighted seriously the foliage of the plants that they were used 

 to protect. Often it was impossible to use them strong enough to kill 

 the insects without at the same time blasting the plants. 



