Feces Getting caught in my dogs hair by area?

You can take some scissors and do a nice close trim job around under the tail. But be really careful about not snipping anything by accident. Just have someone help hold her up with you do it, she's going to most likely try to sit down. Then, you can just trim it up every few weeks, and not pay anything. We trim our own Poodles, which tend to have this problem at times. We have short coated Chihuahua too. Good luck!