Ahtanum is an aroma/flavoring hop variety that is similar to Cascade or Amarillo. It has a citrus and floral character much like cascade with the addition of some piney or earth notes. Grapefruit quality is more forward in than in cascade as well. Alpha acids are lower than cascade at 4 to 6.5% AAU making Ahtanum a good choice for a flavor addition when you do not want to impart quite the bitterness of cascade or amarillo.
Beer styles suited for Ahtanum include American APA, American IPA, Light lagers.