Colorado's state insect, the vibrant Colorado hairstreak, lives among oak trees in that state and the rest of the Four Corners states — Arizona, New Mexico and Utah — as well as eastern Nevada, southern Wyoming and northern Mexico. Colorado hairstreak caterpillars hatch in the spring from eggs laid the previous autumn. Plump and green with white fuzz, they feed on the tender new leaves of their host plant, the Gambel oak (Quercus gambelii), also known as the “scrub oak.” After metamorphosis, the butterfly emerges from its cocoon in late spring or summer. The butterflies dart in and out of the tree's branches, feeding on the tree's sap and fallen raindrops. Mature males look for females receptive to mating. Later, the female lays her eggs singly on the host plant and the cycle of life begins anew not far from their ancestral home. In its entire life, the Colorado hairstreak may travel no more than a few yards from where it hatched. These colorful square non-machineable surcharge stamps were developed in collaboration with the greeting card industry and will be issued in panes of 20 for use on irregular-size envelopes, such as square greeting cards, invitations or announcements. The words “NON-MACHINEABLE SURCHARGE” on the stamp indicate its usage value.