Arapaho blackberry variety

Along-term goal of the University of Arkansas blackberry breeding program has been to develop erect-caned, thornless blackberries that do not require trellis support. The first such cultivar, Navaho, was released from this program in 1988 and quickly became popular with home gardeners and commercial growers. Navaho, however, has two shortcomings - it ripens very late in the season when summer temperatures are high and it produces new canes only sparingly from roots, a characteristic that delays fruiting-row establishment. Arapaho is early ripening, erect, thornless, and quickly establishes a full fruiting row.
A notable feature of Arapaho is its earliness of fruit ripening. It ripens about 10 days earlier than Navaho. The fruiting period of blackberry Arapaho is concentrated into 4 weeks in contrast to the usual 5 to 6 week fruiting period of Navaho.
Arapaho is more prolific in producing primocanes from roots than Navaho. Plants have good resistance to cold injury at temperatures as low as minus 24 C. No orange rust and rosette has been observed on Arapaho when grown in areas of high inoculum. Arapaho can complement Navaho in providing a long harvest season for high-quality thornless blackberries.
This variety is a complement to Navaho, expand the harvest period for high-quality thornless blackberries. Arapaho fruit are short-conic in shape and have bright glossy black color. Fruit are firm, similar to Navaho. The fruit is short conic in shape, bright glossy black in color and medium in size. The fruit is firm at maturity, rating slightly less firm than the Navaho variety but more firm than the Shawnee variety. Storage quality of the fruit is comparable to the Navaho variety and superior to the Shawnee variety. Fruit clusters are medium-large, cymose, and are borne on the periphery of the plant canopy, providing easy access to harvest. Flower fertility is high and clusters are well filled.
An important positive characteristic of Arapaho variety is its small seed size. Seeds are significantly smaller than those of Navaho. The flavor is
sweet and mildly subacid, with a prominent aroma reminiscent of wild blackberries.

Table 1. Сomparison table of Navaho, Shawnee, Choctaw and Arapaho blackberries at the University of Arkansas Fruit Substation, Clarksville

Main features	Cultivar
	Shawnee	Choctaw	Navaho	Arapaho
Harvest date
First	June 5	May 28	June 14	June 3
Last	July 10	June 23	July 25	July 1
Fruit (rating scale of 1 to 10 where 10 is the best)
Seed weight, mg	4.0	2.1	3.6	2.7
Firmness	7.5	7.2	9.3	9.1
Flavor	7.2	8.2	9.8	9.3
Soluble solids, %	8.7	8.3	10.8	9.1
Plant (rating scale of 1 to 10 where 10 is the best)
Vigor	10.0	9.2	7.2	7.7
Winter injury	9.3	7.5	7.9	9.5

Table 2. Yield and average berry yield of Shawnee, Choctaw, Navaho and Arapaho cultivars at three locations in Arkansas

Cultivar	Yield, kg/ha	Berry weight, g
Clarksville
Shawnee	15700	6.9
Choctaw	10600	5.0
Navaho	10800	4.8
Arapaho	6300	5.1
Hope
Shawnee	11000	6.1
Choctaw	12900	4.3
Navaho	4900	4.3
Arapaho	8600	4.7
Fayetteville
Shawnee	14500	6.0
Choctaw	13600	4.5
Navaho	15300	4.8
Arapaho	9500	4.1