THE PINE INVESTIGATION. 319 



KEMEDIES CONSIDERED. 



At first, a remedy against the rapidly spreading ravages of the beetle, 

 seemed out of the question, but when it was found that they had just 

 commenced their attack upon the forests of black spruce and white pine 

 it indicated that possibly some method could be found by which the 

 healthy and more valuable portions of these forests could be protected. 



The "method of cutting and burning the first infested trees to destroy 

 the insects was considered, but it was found that it could not be generally 

 practiced in our West Virginia forests, owing to many difficulties and con- 

 ditions rendering this as well as other like methods impracticable. 



The occurrence of a similar trouble in our spruce forests between 1882 

 and 1889 caused evidently, by the spruce bark beetle (Polygraphus rufipen- 

 nis), was, I have every reason to believe, brought to an end principally by 

 the appearance of some six species of parasites and predaceous insects, 

 which were found preying upon it. This, together with the well known 

 success of the introduction of Vedalia cardinalis from Australia into Cali- 

 fornia, resulting in the destruction of the 7cer?/a, led me to consider 

 methods of combating the destructive pine bark beetle, and to carry into 

 effect a previously contemplated experiment of introducing certain insects 

 from Europe to feed upon some of our injurious bark beetles. 



By correspondence with Oberforester Eichhoff of Strassburg, Germany. 

 I learned that a certain beetle, Clems formicarius L., was a ''great de- 

 stroyer of Scolytids" in the forests there, and from my knowledge of the 

 habits of the nearly-related species, Thanasimus dubius, Fab., I felt that it 

 would be a most desirable species to introduce into our forests to feed upon 

 the destructive pine bark beetle, and possibly check it ravages. There- 

 fore, the experiment of introducing this beneficial European species into 

 our State for this purpose was recommended to our Station officials and to 

 owners of the threatened spruce and white pine forests. This propos- 

 ed experiment was at once approved and the Station, aided by liberal con- 

 tributions from four of the principal lumber companies, sent me to 

 Europe in quest of such insects as, in my judgment, would when intro- 

 duced into our forests, accomplish the desired end. I, therefore, proceed- 

 ed at once to Germany, sailing from New York on August 17, and arriving 

 at Strassburg on August 27, and after visiting some of the principle pine 

 and spruce forests of Aslace, Lorraine and Saxony, in Germany, Schwyz, 

 Lucerne, and the Oberland Bernese Alps in Switzerland, I started back to 

 America on September 25, with over one thousand live specimens of 

 Clerus formicarius, which was found to be especially destructive fco var- 

 ious bark beetles in all of the forests visited. * * * 



The following extracts, translated from an article in German 

 published in "Science" 1 in November, 1892, by Director Camil- 

 lo F. Schaufuss of Meissen, Saxony, will give some additional 

 information: 



"ON THE INTRODUCTION OP THE EUROPEAN BARK BEETLE DESTROYER 

 (CLERUS FORMICARIUS), TO AMERICA." 



* * * * "it h as certainly been very plainly seen in Nature that in her 

 domain equilibrium should be retained. She has therefore placed a limit 

 to the excess of individual animals, in which she causes their enemies to 

 associate. Besides birds, insects have very many other destroyers, especially 



1 Science [N. Y.) Vol. XX, 1892, pp 256-257. 



