My camp, while doing our moop sweep in 2023, found lag bolts from prior years!

2023 was a weird one, because of the heavy rain and so many people not being used to it.

But it also seriously churned the Playa, revealing what was hidden for a whiiile

Marking whiskers, as mentioned, seem like a good solution if you can keep them attached. They are designed to be easily visible on the ground.