Help identifying plum tree

[planetb]

I purchased a new home this summer that came with a couple small plum trees. The plums are starting to ripen as of mid-September in northern Montana. They're relatively small - the largest is about the size of a ping pong ball. Any idea what variety these are?

If the image doesn't load, you can go to http://planetbgardens.com/plum-preserves. I'm going to see how they turn out as preserves in the meantime.

[sgbotsford]

Do they taste good?

It's not brookred or brookgold, or pembina or toka or mount royal.

5 down a zillion to go.

Try Youtube for directions on pruning.