Something Is Producing Many Small, Thumbnail Size Dirt Clods Overnight. Also Occasional Finger Size Holes That Seem To Lead Nowhe

Question

re. I am very familiar with moles and gophers. Clods are scattered over a dirt area approx 5′ in diameter. No loose dirt, only formed small clods. Maybe 10-15 each night. Only one plant close-by with no apparent damage yet, though maybe roots. Some large rocks that will be difficult to move. Can send foto if someone wants to see dirt clods. Been here 30+ years. Never seen this. No ground cover, grass or other cover in the area.

Answer 1

It could be earthworms or other insects. Earthworms tunnel through the dirt, ingesting the soil for organic matter. They leave castings, which dry into small lumps of dirt. Here is more:

https://www.gardeningknowhow.com/composting/vermicomposting/benefits-of-garden-worms.htm