286 WEST VIRGINIA EXPERIMENT STATION 



beetle is (Dendroctonus frontalis.) The red looking grub you sent feeds on 

 this and other insects, therefore you made a mistake in placing it in the 

 bottle with the other specimens, for it has devoured many of them. The 

 large worm probably enters the bark after the tree commences to die. 

 The one you found in the live tree is usually found in the outer bark of 

 such trees, therefore can do no damage. 



There is another insect about three times as large as the small black 

 ones which I suspect as being among the principal ones to blame for the 

 death of the trees. They work under the bark near the root of the tree, 

 sometimes even under the ground. I found them near Romney last sum- 

 mer in perfectly green trees, working in the turpentine under the bark. I 

 also found them under the bark of trees which had recently died ; there- 

 fore, I hope you will look carefully for them and others like them in green 

 and dying trees. Send a bottle full of each kind of the small round-bodied 

 beetles you find in the bark of the trees. 



I may visit your section next month, but if I do not, I would like to ar- 

 range to have you send me by freight some sections from small trees in- 

 fested by certain insects. 



The only remedy we can think of to prevent the spread of the trouble 

 among your timber is to introduce some kind of insect that will destroy 

 the injurious species. I am now arranging to import some parasites from 

 Virginia, Germany and France to put after some of our insect pests." 



Mr. Strayer wrote again on Oct. 18th, 1891, as follows : 



"I send by this mail a box containing several species of bugs, etc., found 

 under the bark of dead, yellow pine (still standing.) The shells of bugs 

 enclosed were all found together in a nest under the bark. The worm like 

 larva was found near the root of the tree. I traced his passage for about 

 four feet until I found him. He left a passage way of at least f inch. The 

 red-headed bug was first put in a vial with the Tomicus, when it immedi- 

 ately attacked the 'cus.' I send chip to show how the chip was literally 

 riddled." 



In repl} r to this letter I said : 



'I have just received yourlelter of the 10th inst., and the box of insects 

 of same date for which please accept thanks. 



The large grub or larva you found in the dead pine is commonly called 

 the Sawyer. When they are boring into the wood, the sound produced 

 resembles that of an auger. The larvae change to beetles in the spring. 

 The beetles then deposit their eggs in the bark of recently cut pine logs or 

 trees, which have commenced to die. The red-headed beetle is (Thana- 

 simus dubius) and the red larvae are the larvae of this same species. 

 This beetle and its larvae feed upon Tomicus and like beetles. 



The shells which you supposed to be that of bugs found in a nest are 

 the empty egg cases of the common wood roach. 



The Tomicus and like beetles are very interesting to me. Am sorry 

 you did not send more of them, I believe that the Dendroctonus terebrans, 

 (like the one you sent to Washington) are the principal insects to blame 

 for the death of your pines. 



The more you send of each species of beetles like Tomicus and Den- 

 droctonus, the better. They belong to a family of beetles called Scoly- 

 tidae containing several hundred species, nearly all of which are more or 

 less injurious to forest and fruit trees. 



I have a correspondent in France and one in Germany with whom I am 

 arranging to import some live parasites of these Scolytids to experiment 

 with in sending them after our injurious species. This seems to be the 

 only practical remedy to be thought of to check or prevent their ravages." 



