First post here, very impressed with the information found here

[jimdad07]

Jimdad,

I am assuming here when you say "poplar" you are refering to "Tulip Poplar" or "Yellow Poplar" and not "Popple" which is a regional term for Aspen.  Aspen should not be used for framing. Yellow Poplar is a strong and light wood and frames well if you can get it to dry correctly and stay straight. That said it is very prone to wide, deep checks.  If you are doing boxed heart framing this is not that much of a concern as the check never passes through the heart but with the way you are sawing, the check could split the timber clean in half. Twisting is also an issue. Try to verify that there is no spiral in the bark of the trees you select.  I once cut some braces out of poplar that were not boxed heat and after they dried, you could split them in half by hand.  Just a few wood fibers were holding them together. 

Poplar is noted for making good siding.  With logs that size you might want to cut the outside off for siding until you reach the size timber you desire wich would be boxed heart center and good for timber framing.

It is actually cottonwood, which up here we call poplar, we don't get aspen that big up here, they normally die off well before the bark gets rough.  The trunk grains are fairly strait in these trees, the crotches were quite high on these trees.  A big problem with what I am doing is the desire to have a new shop built in this style vs. money and availability of materials.  I am hoping to get a hold of some nice strait red oaks that there is an abundance of up here but with so many burning firewood these days, myself included, it is hard to come by before someone else comes in and cuts it up.  I would like to get a few of these at least for some of the main framing.  If I can't then I have to use what I have and what I can afford which isn't a lot right now with mouths to feed.  I hope I don't sound like a goober here with what I am trying to do but as said, I have to work with what I have as best as I can.