What are these mud looking strings hanging from my ceiling

Ceiling Mold Growth Learn the Cause and How to Prevent it - Environix

Get the Look: Hanging Lanterns in the Classroom – KindergartenWorks

What Are Termite Mud Tubes, Signs Of Termite Infestation

Sulphur Cave in Colorado Home To Blood-Red Worm Blobs : Short Wave : NPR

Tragedy at Sand Cave (U.S. National Park Service)

How to Get Rid of a Dirt Dauber Nest

7 Signs of Termites in the Ceiling

Signs of Termites in Drywall, Ceiling, Floor and Bathroom

Termites

Ceiling Mold Growth Learn the Cause and How to Prevent it - Environix

yakisugi-ceiling-outdoor-kitchen Green building concept, Natural building, Timber