Old notes from his program indicated that he evaluated raspberry and blackberry germplasm at an old research facility called McCullers Research Station in southern Wake County. However, in the 1950's the bramble breeding program was shut down and most of the germplasm was lost. We think that he grew 'Mandarin' and other heat tolerant raspberries in this location.
As many people know, wild brambles tend to spread out and become established in forest and field edges. Last week we went on a germplasm expedition to McCullers Crossroads to see if we could find any wild escapes that may have persisted over the decades. We thought that maybe we could find some other heat tolerant raspberry plants or maybe an erect blackberry in a ditch or along a fenceline? But, we found neither one. We found semierect blackberries that could be related to cultivated types that would have been included in the trials there. These had characteristics that suggested that they had 'Himalaya Giant' in their genetic background, like the 'Williams' cultivar released from professor Williams' program. We also found trailing types on one roadside that were similar to 'Carolina' dewberry.