Dragging, those are the kinds of things that happen eventually and why you do need to keep a constant eye on them. I never had Mom eating dirt (though I know of some that have) but she did pour sour milk on her cereal and start eating it before I could get to her. I had to be very careful of what was in the refrigerator because she had no idea if foods were spoiled or not. The deficiencies in her taste sensations didn't help her to determine if it was good food or bad food. The visual perception and processing was deficient as well so she did not pick up on the visual cues. Smell deficiencies rounded out the inability to determine what was eatable. The same thing goes for non eatable items. It may have looked like crumbled up chocolate cookies to her. The texture was about right. Mom did "drink" hand lotion. She called it her "energy drink". She also mixed it with her peanuts!!
To that end I removed or locked up many things from the house that could be confused with foods. Plants, dirt, medications, cleaning supplies, detergents, are all problems when they do not know what to eat or what not to eat. I also put bathroom supplies out of sight with a child proof lock on the cabinet. Mouthwash can be a problem if they drink it. It is like making a house safe for a toddler that puts everything in their mouth. Be glad it was just dirt. That won't hurt her and it could have been much worse