How do caterpillars use silk to stay attached to plants?

Caterpillars use silk to maintain a secure hold on the plants they inhabit. Most larvae continually spin silk threads that adhere to the surfaces on which they live, providing them with an almost unshakable grip.1

This silk is produced by large, paired glands located internally and is extruded through a tubular spinneret situated between the labial palps on the caterpillar's head. As the liquid silk emerges, it hardens upon exposure to air. In addition to providing a grip, caterpillars may use these silk threads for dispersal; very young larvae of some species hang from silk threads to be carried by the wind to new locations.231