A strong relationship between oviposition preference and larval performance in a shoot-galling sawfly

The oviposition preference hierarchy of Euura lasiolepis for Salix lasiolepis shoots of different lengths strongly corresponded with the rank of shoot lengths for larval survival. The more rapidly a shoot was growing the higher the probability that an oviposition site on a shoot would be attacked. Larval survival was highest on long shoots on young ramets. The probability of shoot abscission was negatively related to shoot length, and Euura in galls on abscised shoots invariably died. Intraspecific interactions and willow clone identity, independent of shoot length and ramet age, had relatively small influences on larval survival. Arroyo willow shoots were always attacked in order of length, so that a strong relationship between preference and performance was always maintained. -from Authors