is a Saaz-type hop developed by the U.S. Department of Agriculture (USDA) hop breeding program in Corvallis, Oregon. Sterling originated in 1990 from a cross by Al Haunold between a virus-free female Saaz clone and a male USDA variety with Cascade and a complex European ancestry in its background. Sterling was released by John Henning and Al Haunold in 1999. For a Saaz-type hop, Sterling typically produces a high alpha acid content (8.1%), whereas its beta acid content averages 4.7%. The cohumulone fraction of the alpha acids averages approximately 24%. The essential oil profile, however, is typically Saaz-like, in part because of its relatively high levels of farnesene. Sterling is somewhat susceptible to downy mildew but tolerant of powdery mildew, spider mites, and hop aphids. Sterling plants often exhibit a distinct yellowing of foliage (chlorosis) during intense summer heat.