I have black raspberries (wild) on my property ,They grow and multiply like weeds in the edge of the woods. I have been told they get a mosaic disease and I should not bring them into the garden with my other bramble berries .
They are much smaller than the red and I would guess harder to raise on large farms for profit. They are however very tasty, and if one can stand the mosquitoes , worth picking. They ripen around the first of July here and it always seems to be prime mosquito time.