These are Black Raspberries. Many people refer to them as “Black Caps”. As you can see in the photo, when the fruit is picked, the white core remains attached to the plant. This is the simplest way to tell them from Blackberries.
Another way to tell the two berries apart ( in my area of upstate New York and western Massachusetts), is according to their time of ripening. Black Raspberries appear in June and Blackberries are in August.
Black Raspberries are a small fruit and grow in sparse numbers per bush while Blackberries can yield gallons of fruit in a similar space. I’ve found it hard to find significant patches of wild Black Raspberries. They are susceptible to many blights which also plague wild Raspberries. One final note, they are far less painful to harvest than Blackberries, simply because, their thorns are much smaller and their fruit tends to grow outwardly.
A Black Raspberry patch is indeed a great find!
Related articles
- National Raspberry Day (ireport.cnn.com)
Sillyfrog's Blog 
O’ I Love Black Raspberries!!!!
We have some but encouraging their spread has been difficult. I will persevere!
It’ll be worth it…Charge!!!!!
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