Andrew M. Liebhold
U.S. Forest Service Northern Research Station
180 Canfield Street
Morgantown, WV 26505
E-mail: aliebhold@fs.fed.us

and

Ruth Plymale
Department of Biology
Ouachita Baptist University
410 Ouachita St.
Arkadelphia, Arkansas 71998 USA
E-mail: plymaler@obu.edu

Joseph S. Elkinton
Department of Plant, Soil & Insect Sciences
University of Massachusetts
Amherst, MA 01003 USA
E-mail: elkinton@ent.umass.edu

Ann E. Hajek
Department of Entomology
Cornell University
Ithaca, NY 14853-2601 USA
E-mail: aeh4@cornell.edu

glm.sas (MD5: c946a1840dd18caadcf2dfc663ab664e)

The file glm.sas contains SAS code for testing the significance of differences in the linear relationship of season-long LdNPV mortality to log10 egg mass density collected before and after 1989 (the point at which E. maimaiga appeared in North American gypsy moth populations).