Dogs eating foxtails

Wogster, by "fox tails" do you mean a mat of fur?  I don't know why your dog would eat them unless there is something that smelled funny stuck in there.  If the matt was pulling on the dogs skin, the dog may try and pull it out himself.

At this time of year many dogs are shedding a lot which can cause a mat to form.  Regular brushing, even daily for dogs with long hair or a thick undercoat will help reduce the shedding and chances of mats forming.  If your dog has a mat that is close to the skin, it is best to have a groomer or vet tech shave it off.  It is never a good idea to use scissors to remove mats as it is very easy to cut the animal and likely that they will not hold still.