PEACTICAL ENTOMOLOGY. 435 



AKTIFICIAL EEMEDIES. 



I have tried, quite thoroughly, several insecticides. I find nothing equal 



to the kerosene mixture. Lye and even soap solution will destroy the young 

 lice, but not so surely as the kerosene emulsion. I have also tried kerosene 

 and milk, but do not like it as well as the kerosene and soap. Any kind of 

 soap may be used. I have found the following very efficient : One quart of 

 soft soap and two gallons of water are heated to the boiling point, when one 

 pint of kerosene oil is immediately stirred in and all well mixed. 



This is doubtless the best way to prepare kerosene emulsion, and thus pre- 

 pared it is very valuable as an insecticide. When applied to foliage this does 

 not seem to injure it; in fact, I have sometimes thought it was beneficial to the 

 plant, aside from the effect it had in killing insects. In applying this to the 

 scale lice it should be thi'own on with considerable force. This is true in case 

 of all insects. If we turn the liquid on with a sprinkler it does not reach all 

 the insects, at least so as to destroy, while if forced on as a fine spray it reaches 

 all and carries death along with it. 



To apply the liquid a common force pump or a fountain pump serves well. 

 The cyclone nozzle, invented by Dr. C. V. Kiley, throws a fine spray, and 

 uses the material effectively and economically. The Woodason spray bellows 

 has the same to recommend it. AVith it I have sprayed quite a large tree 

 with a pint of liquid. 



In fighting these bark lice the sooner the application is made after the lice 

 are all hatched the better. I have found that the kerosene mixture applied to 

 the young lice killed every one, while if applied after a few weeks the effect 

 was not so great unless more of the liquid was used. 



If it is desired to kill the mature lice in April and early May, when the 

 scales are so plainly visible underneath the branches and twigs of the trees we 

 must resort to other means. I have found that by use of a broom with a long 

 handle, dipped in soap suds, lye, or the kerosene mixture, I could soon rub 

 off the scales and thus destroy millions of eggs in a very brief time. I did not 

 succeed in killing these mature lice by simply spraying them. President 

 Edward Orton writes me that in Columbus, Ohio, where these lice have been 

 very injurious to the maples, both the mature lice covering the eggs as well as 

 the young lice may be killed very quickly by turning on to the tree, the hose 

 from the city water works. In cities this will be an easy cure. 



Unless the natural enemies soon extirpate these lice it will pay well to 

 fight the lice as suggested above. The absorbing of the sap by the millions of 

 little suckers will soon devitalize and ruin the trees. The expense of des- 

 troying the lice is not great, as such trees as our ordinary shade trees are 

 rapidly treated. By use of a wagon to draw the liquid, and a force pump 

 fastened to the barrels containing it, and a fine rose or the cyclone nozzle 

 the work is rapid and effective, while the cost of the liquid is very slight 

 indeed. 



SECEETION OF NECTAR. 



Another feature of these lice is not without its practical significance. I 

 refer to the nectar which they secrete. When very abundant as they have 

 been the past season (1884) in several parts of the country, the bees gather large 

 quantities of it. The flavor of the honey if J:here is not too much of this 

 secretion is not unpleasant. While the fact that the bees are so actively 

 employed in storing all through May, leads to rapid breeding. So that there 

 are very populous colonies at the dawn of the clover season. In case these 



55 



