Puppy eating absolutely everything on walks

So, my Pom is 4 months old now and she’s obsessed with picking up and trying to eat everything on the floor (sticks, plants, rocks, bird shits… since she’s starting to lose her puppy hair, she will sometimes try to eat that too). At first I thought it would be something she would grow out of naturally, but it’s turning potty training into a chore and idk if I should take action. Advice would be appreciated, thanks in advance.