what kind of grape?

I have two grape vines which were well established when I purchased my house almost 14 years ago. They are green grapes but they taste like concord grapes to me. Any idea what they are?

 

There are two varieties of concord: the purple and the white.

 

Oops! I did not know that. Thanks!

 

They could be any of a number of varieties.

You may have Niagara or if its seedless possibly Himrod or Interlaken.

Concord grapes are a specific variety used mostly for grape jam or Welchs grape juice.

It is also used sometimes to describe any purple fruited labrusca type grape.


http://en.wikipedia.org/wiki/Vitis_labrusca

Hope this helps.

Cheers