I am an average to below average yard maintainer, and have been noticing bumps in my yard in the past few years that seem to be getting worse. They make it uncomfortable to walk acoss my lawn barefoot anymore. What might be the cause of these mounds? Moles or other animals? And what can be done to get rid of or prevent this?
Yes, it sounds like moles are invading your yard! They dig tunnels just under the surface of the ground and excavate the dirt as they go, leaving mounds of sort yard that won't grow grass well and can be a real tripping hazard to walk through.
The good news is that they are easy to deal with - moles are there to look for food, usually grubs, which are small worm-like insects. Get rid of the grubs and you'll get rid of the moles. I'd recommend you treat the lawn with Grubex, and take it from there.