following regions in the western part of Tamil Nadu: Coimbatore , Erode , Gobi , Tirupur , Pollachi , Nilgiris , Udumalai , Sathy , Salem , Attur , Kallakurichi , Karur , Namakkal , Rasipuram , Thiruchengode , Palani , Dharapuram , Kangeyam , Avinashi , Omalur , Dharmapuri ,