The true Katydid (Pterophylla camellifolia) maybe the loudest and most recognizable sound in the late fall deciduous forest calling Katy-did! Katy didn't, Katydid. There loud calls have different patterns in different parts of the country and vary with temperature. Katydids are often heard but seldom seen because they live high in the upper canopy and practically do not fly preferring to hop or crawl. What this video and learn more about our familiar summer night singer! Learn to recognize sounds in the night forest!