Often, after I've picked up my dog and carried her, her paws make
darkish marks on my Tshirt which I cannot get out doing a normal
laundry. I have to really apply elbow grease and various stain removers
to get the marks out.

Does this happen to you, and if yes, have you found a way to easily get
the marks out?

BTW, she's walking on grass, asphalt, concrete and dirt that may or may
not contain rocks and leaves. She seems to be good at avoiding other
dogs' stool. she gets a bath every two weeks (due to skin condition).