If its the upper side of the tail near where the tail joins the body it could be a problem with the sebaceous gland on the tail. You can see if cleaning the area off with betadine or peroxied an putting some neosporin or triple antibiotic ointment on it will help. You can read about issues with this gland here
http://animalpetdoctor.homestead.com/bacterialskin.html in the section on Stud Tail (just a name nothing to do with the sex of animals having the problem).
Another common reason for tail chewing is flea bite allergy. If she is not on flea prevention this could be the problem too. For that you need to get rid of the fleas and maybe treat with steroids to control the itching. You may have to see the vet for either condition to get the best meds to treat the problem.
And if its right under the tail she is licking then it could be an anal sac issue and you can read about that here
www.marvistavet.com/html/body_anal_sacs.html
Hope this helps you!
Edited by NHolmes on August 20 2005 at 1:24 PM
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