Per LB CAD
Yakima Valley bred Ahtanum™ is sweet and peppery with a piney-citrus aspect. Warmly aromatic and moderately bittering, Ahtanum™ is a hop of distinction. It is often likened to Cascade though without going that far, it makes more sense to say that Cascade may be an acceptable substitute. In comparison, Ahtanum™ is less bitter, its alpha acids are lower and its grapefruit essence is significantly more pronounced. It really is more akin to Willamette, with its notes of lemon and grapefruit. Ahtanum’s distinct citrus character led to it being used as the singular hop in Dogfish Head’s Blood Orange Heffeweisen and Stone Brewing’s Pale Ale.
Alpha - 4% - 6.3%
Descriptions provided by the awesome Hopslist.com