Submitted to: Fruit Varieties Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/22/1998
Publication Date: N/A
Interpretive Summary: Improved thornless blackberry varieties are produced by breeders to meet the demands of growers who wish to maintain an economic advantage in the marketplace. We have introduced the variety Chester Thornless for growers from the Middle Atlantic area to Illinois and in central California to Washington on the Pacific Coast to fill a niche for a high quality, late ripening local market and shipping variety with resistance to cane blight disease. Chester Thornless is vigorous, winter hardy, and high yielding. Its fruit is large with good color, flavor, and firmness. Its fruit does not soften or lose color on hot, sunny and humid days and, because it has a longer shelf-life than other thornless blackberries, fruit can be shipped to wholesale and retail markets. High yields of large, firm, and flavorful fruit give Chester Thornless an economic advantage to growers in its areas of adaptation. Commercial U-pick, roadside-market, and retail-market growers will and have benefitted from the introduction of this variety.
Technical Abstract: Chester Thornless is a very vigorous, productive, large fruited, moderately winterhardy thornless blackberry cultivar [Rubus sp., subgenus Rubus (Eubatus)] released jointly by the Agricultural Research Service, USDA, Illinois Agricultural Experiment Station, The Ohio Agricultural Research and Development Center, and Maryland Agricultural Experiment Station in 1985. It is well adapted south of a line extending from western Maryland, through central Ohio, to Urbana, Illinois in the eastern United States and to portions of the West Coast of the United States. Chester Thornless is as productive as Hull Thornless and is similar in fruit size, color, flavor, firmness, quality, and seed size. Its fruit does not soften or lose color on hot, sunny and humid days and ships well to distant markets. Chester Thornless has proven to be valuable to pick-your-own and back-yard growers, as well as to commercial growers. The outstanding characteristics of Chester Thornless are plant hardiness and disease resistance, and high yields of large fruit of good quality. It is recommended as a replacement for Thornfree blackberry in USDA hardiness zones 5- 7 and possibly in zones 8 and 9.