Hops supply beer's distinctive aroma and the zesty bitterness that balances the sweetness of the malted barley. The original Tettnanger variety can be grown in the U.S., but it does not yield as well here as in its homeland. Santiam yields twice the hops as Tettnanger when grown in Oregon, Washington and Idaho, the prime U.S. hop-growing areas. Santiam is also the world's first naturally seedless Tettnang-type hop. Brewers want seedless hops because seeds can add undesired oils to beer.
Seeds also add useless weight, complicating pricing negotiations between brewers and growers.
At least one-third of the hops in American brews have ARS origin. High cohumulone levels can cause an off-taste in beer. Horizon provides both. It contains high levels of alpha acids, which provide bitterness. Horizon was originally developed two decades ago but was not publicly released because it is susceptible to downy mildew.