That looks like Bartlett. Many pears have that approximate shape so it is not a definite, but given how common Bartlett is and the shape, chances are looking pretty good that is what you have.

Scott

I've just read at Trees of Antiquity that Bartlett are self-fertile, but this tree has not produced in many years until this year with the hand-pollination.

MHG, according to the book "Pear Production and Handling", 2007, Bartlett is self-sterile but in California they can set fruit without pollination at all (parthenocarpic). It also mentions that this behavior seems to be limited to parts of California and Oregon .. no Colorado in there.

Scott

Well, that makes sense then. Thank you, scottfsmith! I have never heard of this before! I learned something today and it's only 6:35 a.m.!

I'll call my tree a Bartlett until I know otherwise. I've grafted a few varieties onto it for pollination, but don't know if any of them took yet.