Narrative
Advantages of Crystal are its excellent vigor and spring regrowth, high yield potential, and brewing quality traits similar to certain imported European aroma hops. Crystal matures medium-late (about September 5-10) in western Oregon. It is well adapted to the major hop growing areas of Oregon, Washington, and Idaho. Shoots rapidly climb a supporting string and reach the top wire (18 ft) about 4-5 weeks after training. Sidearms average from 24-36 inches in length with ample secondary and tertiary branching and abundant cone set. Starting in 1985 Crystal's yields in small nursery plots near Corvallis ranged from 800 to 2244 lbs/acre, with a 7-year average of 1202 lbs/acre. Yields in the large 3-acre commercial plots near Salem, Oregon, ranged from 1186-2542 lbs/acre since 1988 (5-year average: 2038 lbs/acre). The 3-year production average (1988-91) for Washington and Idaho was 1166 and 1760 lbs/acre, respectively. Crystal's alpha and beta acids content during the testing period averaged 6.0 and 6.7 percent, respectively, with a cohumulone content of 21 percent and a colupulone content of 35-40 percent. The alpha ratio, a measure of the ratio alpha:beta, was 47. The relative proportions of alpha and beta acids, the low cohumulone and colupulone content of Crystal are similar to those of Saazer. In contrast to Saazer, Crystal does not have farnesene in its essential oil. Crystal has relatively poor storage stability of its soft resins. In controlled room temperature storage tests, about 50 percent of the original alpha acids was transformed to other products not measured spectrophotometrically. The content of essential oils of Crystal hops is relatively high, ranging from 0.77-2.14 ml/100 g, with a seven-year average of 1-38 ml/100 g. Oil composition percentages ranged from 40-65 for myrcene, 18-24 for humulene, and 4-8 for caryophyllene, with only trace amounts (0.1 percent) of farnesene, resulting in a ratio of humulene:caryophyllene of about 3.60, characteristic of imported European aroma hops.Alpha acids content in commercial test plots in Oregon, Washington, and Idaho averaged 3.6, 3.0, and 1.7 percent, significantly lower than in the initial Oregon nursery test plots. This may in part have been due to improper handling after harvest as indicated by an abnormally high Hop Storage Index (HSI) for one Washington and two Idaho harvests (0.47, 0.59, and 0.92, respectively). Beta acids content averaged 6.3, 4.8, and 4.6 percent, respectively, while cohumulone content ranged from 19-23 percent of the alpha acids.Crystal has columnar growth habit, but due to the vigorous sidearm development and commercial stringing, individual plants grow together forming a nearly solid canopy late in the season. In Oregon, Crystal showed some hop downy mildew early in the season, particularly on dense basal shoot development. Vigorous suckering after training is recommended to keep downy mildew under control early in the season. The disease was readily controlled with fungicides authorized for use on hops. Downy mildew cone infection was observed during only one Oregon growing season and was controlled with timely fungicide applications. Crown die-out due to downy mildew was never observed in Crystal's perennial rootstock.During all trials no Verticillium wilt symptoms were observed. Crystal's major advantages are high yield potential and quality traits similar to prized European aroma hops. The major interest in Crystal has come from small brewers whose access to imported European aroma hops sometimes is limited. Crystal's market initially may be limited despite the rapid growth of many small regional brewers and their specialty beers. -- USDA Release Notice, 1993.
Cultivar Synonym= USDA 21490