Turtle in the garden

This morning as dh was leaving he saw a turtle in our garden. After going out to look at it I think it was a snapping turtle. There is a pond just through the woods. It seemed to be laying eggs. DH was worried that it would devour all the new plants he's been putting out. Do snappers eat plants? We have seen a couple terrapins last year and I know they like veggies but so far this year we haven't seen any.