Peterson Field Guide to Eastern Moths are still unknown, and hence by recording life history information, preserving, and photographing immature stages, even the casual observer or backyard naturalist has the opportunity to make important entomological contributions. As an alternative, placing larvae into water that has been brought to a rolling boil and removed from the heat will yield excellent specimens. Some success may be obtained by placing caterpillars in a self-defrosting freezer for several months. Although much of the color may be preserved in this way, the specimens end up shrunken and inflexible and are not especially useful as study specimens for taxonomic study. Many caterpillar pigments are lost in fluids.
Greens seem to be especially ephemeral in preserved material.
The almost immediate color losses that accompany the fluid preservation of loopers can be most disconcerting. Photographs or other types of image-capturing techniques provide the best means of documenting the coloration of living individuals. Preserved collections should be labeled in full with locality, date of collection, and host and cross referenced to any photographs or reared material.