Methods of ablating mucosal tissue in an alimentary canal are provided. The methods can include the steps of (i) providing an ablation device comprising a tissue ablation source; (ii) positioning at least a portion of the ablation device at a mucosal tissue surface of the alimentary canal; (iii) delivering a sufficient amount of the source for tissue ablation to the mucosal tissue surface to create a lesion in the mucosal tissue. In one implementation the methods include a step of providing a radiofrequency (RF) energy delivery device.