OF WASHINGTON. 59 



present. I have recently been much interested in the attacks 

 of these beetles on certain large trees, between thirty and forty 

 feet high, which I transplanted last February to my new 

 home, Sunbury, on Washington Heights. The trees specially 

 attacked were a swamp oak and a chestnut, both of these trees 

 being on the west of my residence. It so happens that the 

 ground on the east was largely filled-in or made ground, while 

 that on the west was, on the contrary, simply leveled off. This 

 proved to be badly infested with Lachnosterna, and I have 

 had great difficulty in preventing the entire defoliation of the 

 two trees mentioned. The first species to appear was L. hir- 

 ticula, and this was by far the most abundant and injurious 

 species the only other species noticed being fusca. It was 

 evident from the beginning that the trees in question could not 

 withstand the combined check resulting from the transplant 

 ing and the defoliation by the insects, so that I made strenu 

 ous efforts to thwart the latter. Smudges would doubtless 

 have been efficacious if they could have been employed, but 

 they were rendered impracticable owing, first, to the height of 

 the trees and then to the prevalence of winds. With the assist 

 ance of Mr. Marlatt I made various experiments with insecti 

 cides, the chief of which were as follows : 



(1) The trees were sprayed with a strong whale oil and 

 tobacco soap solution about five o'clock in the evening. The 

 spraying was satisfactorily and thoroughly done by means of 

 the bamboo extension rod. A rain which followed during the 

 night somewhat interfered with the experiment, but not until 

 after the beetles had appeared and cut off a quantity of 

 the leaves showing the practical inutility of the appli 

 cation. 



(2) London purple was applied at the rate of one pound to 

 one hundred and twenty-five gallons of water, a stronger mix 

 ture not being advisable, owing to the tender character of the 

 foliage, especially' of the oak. This application was also 

 satisfactorily and thoroughly made, not a leaf having escaped 

 the spraying. There is no doubt but that this spraying 

 resulted in the destroying of a considerable number of beetles, 

 since two dead ones were found under the oak tree next day. 

 It did not, however, limit the onslaught, and I made up my 

 mind that it would be futile to endeavor to prevent the attacks 

 of the beetle by any insecticide or other means at command, 

 for the simple reason that the beetles would escape nightly 

 from the soil, swarming more or less numerously around these 

 two trees. 



(3) I also endeavored to attract the beetles by lamps float 

 ing in a tub of water having a scum of kerosene. The num- 



