Identification. – Look for "inch worm" type larvae on needles from late June to September. The first two instars have smooth bodies and are light brown with yellow stripes along the sides. Instars III through V have varying shades of brown without stripes and have numerous tubercles the length of the body. They resemble pine twigs (fig. 135). Mature larvae are up to 1-1/2 inches long. Dark brown pupae may be found in the duff from September to June. Adults, appearing in early summer, are mottled gray-brown with zigzag markings on wings and wingspan of up to 2 inches. Eggs are laid in clusters on the needles and stems in early July.