Rubus ursinus 'Aughinbaugh' is a historic and highly significant cultivar of the California blackberry (or Pacific blackberry), a trailing species in the family Rosaceae. The wild parent species is native to western North America, spanning from British Columbia down through California. The genus name Rubus is Latin for "bramble," while the species epithet ursinus means "pertaining to bears," a nod to the animal's fondness for the fruit. The cultivar 'Aughinbaugh' was selected from the wild in San Jose, California, during the late 19th century by a pioneer horticulturist named California Aughinbaugh. Historically, this specific cultivar is monumental in pomology: it was the maternal parent used by Judge James Logan to create the Loganberry (Rubus × loganobaccus), making it a cornerstone ancestor of many modern caneberry hybrids, including the boysenberry and marionberry.

The Aughinbaugh blackberry produces fruit that is highly celebrated for its exceptional, complex flavor. The blackberries are oblong, glossy, and deep purplish-black when fully ripe. Because it is a true blackberry, the receptacle (core) stays within the fruit when harvested. The flavor is a sophisticated balance of intense sweetness and a sharp, musky acidity, carrying the wild "forest" notes characteristic of the Pacific native brambles. Historically, it was sold in San Francisco markets as a premium dessert fruit. Today, because it has been largely superseded by its more productive hybrid descendants, it is primarily grown by heirloom fruit preservationists and used for artisanal pies, preserves, and specialized syrups.