American Hops, History, is essentially the evolution of a collection of native wild-type genotypes, a few transplanted European varieties cultivated from imported rhizomes, and US-developed cultivars. The resulting portfolio of hop varieties is used for both aroma and bittering in brewing. A number of private and publicly developed cultivars have been released by US breeding programs. These include Willamette, Nugget, Cascade, and Galena. American hops are genetically quite variable, which is not surprising considering their diverse derivations from both native American and European genetic sources. As hop cultivation spread out from its origin in central Europe, growers undoubtedly selected those hop plants that seemed best adapted to local growing conditions and that were most desired by the local breweries. These early hop selections were likely chosen from among local wild hop plants that had some favorable characteristics for brewing and perhaps desirable agronomic traits as well. In time, the most suitable plants would prevail and eventually transplanted to other growing areas. Settlers played an important role in transporting desirable hop genotypes into new growing areas. The same goes for the migration of European hops overseas into North America as well as the migration of hops from the East to the West Coast of the New World.

Brewing in North America began with the arrival of European settlers, who considered beer a staple of life, nearly as important as bread and water. Although hops were occasionally imported from Europe, the early pioneers carefully evaluated their potential homestead sites and the surrounding countryside not only in terms of the suitability for growing grain and raising cattle, but also for the availability of wild hops for beer brewing. They likely selected the best native hop plants around them, just as their European ancestors had done. The first cultivated hops were introduced into the United States from Europe by the Massachusetts Company in 1629 to stabilize local hop availability. Hop cultivation spread along the Eastern seaboard as new towns and communities provided support for hop production. The Puritans, for example, were such successful hop producers that they could eventually ship excess hops to the Quakers in Philadelphia. The Puritans also created a system of small land grants for hop gardens.

The soil in much of New England was not as productive as in the Ohio Valley, which is why New England farmers experimented with specialty crops, including hops. This effort coincided with a rise in commercial brewing on the East Coast and thus a ready market for New England hops. Massachusetts became an important hop growing region, in part because of an 1806 law that required inspection and grading of all hops produced for export. Hops that passed this inspection were considered of the highest quality in the United States, and growers were able to obtain premium prices for them. Thus, by the late 1700s and early 1800s, the New England states became the dominant American hop growing region. At its peak, in 1836, New England hop production reached 654,100 kg (1,441,936 lb), a substantial amount considering that hops were primarily hand-picked at that time.

New York State hops quickly gained a reputation for high quality for several reasons. In 1819, New York instituted an inspection law for hops similar to the earlier one in Massachusetts. Then, in 1825, the Erie Canal opened, which provided convenient shipping from Albany to the midwestern United States. Finally, a series of crop failures in England dried up hop imports and forced American breweries to rely on domestic hops. By 1839, New York produced approximately 32% of US-grown hops, but 20 years later, that amount had risen to 88%.

As the US population continued to grow and expand westward, demand for beer, and the raw ingredients for beer, also grew. Because hop production was very profitable, growers in other states soon tried to plant it. By 1850, hops were being cultivated as far south as Virginia, Alabama, Arkansas, Georgia, and Mississippi and as far west as Ohio, Wisconsin, Michigan, Iowa, and Wisconsin, whose major city, Milwaukee, was about to take off as America’s beer capital. See milwaukee, wi. A major aphid outbreak in Eastern hop yards turned out to be a boon for Wisconsin growers and gave them a major toehold in the market. In 1867 Sauk County in Wisconsin produced some 1,814,400 kg (4,000,000 lb). To put this in perspective, this is about the same amount that is currently produced in the Tettnang region of Germany in an average year. See tettnang hop region. Recurring aphid infestations and downy mildew problems eventually caused the New York hop production to decline, and by 1899, the Pacific Coast states had already surpassed it. When Prohibition was imposed in the United States at the end of World War I, hop growing in New York was abandoned for good. See prohibition.

Hop production began on the Pacific Coast sometime around 1850 when hop yards in Oregon and California were established. The hop industry there grew quickly in the 1870s and 1880s, in part through exports, because of disastrous harvests in Europe during that time. Also, California growers in particular had an agronomic advantage over their eastern American counterparts because the dry summers and mild winters allowed a significant hop crop within a year from planting, whereas it typically took 3 years to produce the first crop in the East. Although there were some outbreaks of hop aphids and red spider mites in California, yields were generally quite good. California growers were also the first in the United States to adopt the high-trellis system for hop production on a large scale. It greatly reduced production costs by eliminating the need to replace hop poles every year. Hop yields in Oregon were not as high as those in California or Washington, but the quality was generally very good. Oregon-grown Fuggle even became popular in England. See fuggle (hop). Much of the Oregon acreage was devoted to the cultivation of Late Cluster, a likely derivative of the English Cluster, with the rest planted with Early Cluster and Fuggle. By the early 1900s, Oregon surpassed both California and New York to become the top hop-producing state, a position that the state held well into the 1940s.

A little more than a decade after hop growing had taken hold in California and Oregon, farmers in the Puyallup Valley of western Washington State experimented with raising hops. Because the soils were fertile and insect infestations low, yields there turned out to be excellent. Records indicate harvests of 1,800 kg/ha (roughly 1,600 lb/acre). Hop production moved into Washington’s Yakima Valley in the mid-1870s. The Yakima area was even warmer and drier than the Puyallup Valley, which made hop aphids less of a problem. See yakima valley hop region. By the mid-1890s, the Yakima Valley was already the largest hop-growing area in Washington State; since the 1940s, it has been the principal hop-growing region of the United States.

Whereas the early settlers in the New World had to rely on indigenous hop plants or on plants generated from imported rhizomes, starting in the late 1800s, systematic breeding programs began creating new cultivars either from successful European varieties or from progeny of European cultivars hybridized to indigenous native American hops. Late Cluster, an important early American hop, is thought to have been a hybrid of English Cluster and a native American male hop plant. Early Cluster is believed to have arisen as a mutant found in an Oregon-grown Late Cluster yard around 1908. Although these origins of the old hop cultivars cannot be determined with certainty, many of them have served as genetic foundations for modern hop cultivars.

Cultivated hop (Humulus lupulus L.) is composed of five botanical varieties: Hl var lupuloides, Hl var neomexicanus, and Hl var pubescens, all from North America; Hl var lupulus from Europe; and Hl var cordifolius from eastern Asia and Japan. According to recent genetic analysis, the three North American Humulus botanical varieties contain the greatest genetic diversity, whereas the European group is the most homogenous. Recent molecular genetics–based research into hop cultivars, breeding lines, and male accessions has revealed that all hop cultivars derive from only two genetic sources—purely European ancestry and hybrids of European and native American ancestry.

The US government sought to establish a hop breeding program in 1904 but abandoned the effort almost immediately. It took until 1931 for the US government to launch a successful hop breeding program in Oregon. This program is still in operation today, as part of the U.S. Department of Agriculture Agricultural Research Service (USDA-ARS). It is located on the campus of Oregon State University in Corvallis. Many successful hop cultivars have been released by the program, some in cooperation with other research institutions. Several private hop breeding programs are also active today, and many have produced commercially successful—and generally patented—hop cultivars.

Today, hop cultivars developed for the American market are bred either as replacements of previously successful cultivars or as new cultivars with significantly different trait profiles. For example, the cultivar Willamette was developed and released by the USDA-ARS program in 1976 as a Fuggle replacement. Fuggle is an English cultivar released in 1875 with a pleasing aroma profile. It has been very popular worldwide, but has poor agronomic characteristics and generates low yields. The very popular Cascade is an American original, too. Its unique, grapefruit-like profile has become the signature aroma and flavor of many North American craft beers. Cascade was developed and released by the USDA-ARS program in 1972. Like Willamette, it contains some Fuggle heritage and probably some native American ancestry as well.

From a global perspective, the American hop industry is, of course, relatively young compared with the well-established and tradition-rich European hop industry. Nonetheless, a dynamic and growing craft beer movement, a substantial and genetically diverse pool of native varieties and their hybrids and descendants, and an active hop research community all bode well for the future of American hop farming, the American hop industry, and the American brewing industry.