Eastern Tent Caterpillar nest on Walnut Tree, golden ratio

eastern tent caterpillar web webworm bagworms nest defoliation tree cocoon pupal nature malacosoma americanum forest insect invasive silken environmental moth bugs thread colony silk creepy mottephobia leaves fall crop damage aposematic autumn caterpillar damage larva natural light toxic pest canadian urticate communal walnut golden ratio destruction white distasteful irritant striped