Modest Sphinx Moth (Pachysphinx modesta): These sphinx moths are found along rivers and on moist mountainsides; generally, anywhere the host plants grow. The larvae feed on leaves of poplar, aspen, cottonwood (all Populus spp.), and willow (Salix spp.). Once they emerge from the cocoon, the adults do not feed at all. Photo by Matt Schaefer on 6/23/18 near Stevensville, MT.