December, '12] BUTTRICK: BLACK HILLS TIMBER INSECTS 459 



CURV£ I. "'^"-'* 



Scosof) a?id 



ahunaunce 



of Lorers 



^on f^ /far Afi f //«/ '< Jujie jZJy Auij Se^t-' JOct TVov Oec 



Growing Seoso?? - 



^^ /7y/^y S^Qion /f/»6roiiajbeef/es 



CURVE E 



TfcT 



Decree o/ /i//esfQf/on A>//^otvti7^ Ara at c/iY/erent Sea6on6 



CURS/E Rr 



/^,rs/ Ye 



YJmter Sfrrin^ Svmmer Fa// V/infCr S/^rfrjy SuryirnCr /^a// ^v 



ProbaJj/e Tate 0/ c/es/ 7'uc^/ o?y />y /borers o/ f/m /)e?^ trilled 

 at d/ f/Cr^ /?t Sfaso^s 



