Navajo

Correctly spelled 'Navaho', this was the University of Arkansas's first thornless release and the first genuinely erect thornless blackberry, described by Moore and Clark in HortScience 24 in 1989. It came from a hand-pollinated cross of Arkansas selections 583 x 631 made in 1977 at the Fruit Substation in Clarksville; seed was germinated in 1978 and the seedling Ark. 1172 was selected in 1980 for thornless, erect canes and high fruit quality, with the thornless gene inherited from Merton Thornless. Its selling points are sweetness and season extension rather than size: the berries are small to medium but among the sweetest of the older Arkansas cultivars, and they ripen late over an unusually long picking period. It is still planted for farmers markets and u-picks that want fruit after the main erect cultivars have finished. Its high chilling requirement, however, makes it a poor choice in low-chill regions.