Hello, i have a sulcata tortoise around 6 years old he's a juvenile. Around a 50 lb male. I live in colorado so the climate is pretty dry not much rainfall maybe once or twice a week. He has a little burrow he likes to sleep in and dig at, maybe a foot or two long he couldn't get further because of roots from the tree which is a pine tree so it does have sap. Just clarifying if its buildup of dirt and sap on his shell or if it's a sign of shell rot i cant take chances. If you need better pictures please ask.