A type of
edible blackberry grown in the northwest state of
Oregon, USA. Also referred to as the Marion
blackberry or Marionberry (with the M capitalized).
The marionberry is a cross between the Chehalem and Olallieberry blackberries and was first developed in Marion County, Oregon, from which it gets its name.
It's apparently good in jams and pies (from the many marionberry recipes one can find from a quick Yahoo search).
I found a small jar in the back of the food closet (might have been there for 10+ years...) that must have come from a gift basket. I had never heard of the marionberry before, but I can tell you it tastes damn good on waffles.
Not related to Arkansas representative Marion Berry, nor former Washington, D.C. mayor Marion Barry.
Historical information taken from www.oregon-berries.com