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The locutil borer (Cyllene robinin: Fortit.) .1. I). /lo/jkins. . 1 



Object of paper , 1 



Economic importance of the insect 1 



Investigations I 



Character of the insect and its work 2 



Extent of damage or loss 3 



Possibilities of preventing losses 3 



Historical references 3 



Observations by the writer, 1890-1905 7 



Observations by members of the Forest Service 9 



Recent observations by the writer 9 



Suggestions for controlling the insect and preventing losses 11 



Suggestions for propagating borer-resistant trees 13 



Publications relating to the locust borer 15 



The western pine-destroying barkbeetle {Dendroctonus brevicomis I.ec), 



J. L. Webb.. 17 



Introiluction 17 



Death of the pine caused by the western pine-destroying barkbeetle IS 



Character of the insect and its work IS 



Distribution 19 



Extent of damage and losses 19 



Possibilities of preventing losses .• 20 



Early history of the species 20 



Observations by Hopkins, 1899-1904 21 



Observations by II. E. Burke. 1904 23 



Observations by the writer. 1905 23 



Life history and habits of the insect 23 



Natural enemies 27 



Methods of combating the insert 27 



Summary 29 



Publications relating to the western pine-destroying barkbeetle 30 



Additional data on the locust borer (Cyllene robinin- Forst.) 4. D. Hopkins . . 31 



Seasonal history 31 



Habit.s of larviP and adults 33 



Economic features 34 



Natural enemies 35 



Methods of control 36 



The southern pine sawyer ( Monohammus titillator Fab. i J. L. Webb. . 41 



Introtluction 41 



History 42 



Distribution 43 



Host plants 43 



Condition of trees aftaeked 43 



Injury to pine forests by storms ,. 43 



o The five papers constituting this bulletin were issued in separate form on June 13 



and August IS. lOOti; March 5. 1907: and Novemlier 10 and December 4. 1009. respec- 

 tively. 



v 



