These are poplar logs… one of my favorites.
Poplar logs are often among the widest logs found on old cabins.
Poplar is an abundant species of wood, it grows straight and relatively knot-free, and it is a joy to hew and notch. These massive logs tend to “soften” in appearance as they age and are quite tempting to caress with the hand as they will not splinter. They are also among the best logs for insulation R-values.
I have no idea why log cabin kit homes do not offer poplar logs… it’s baffling to me.
If you look closely you can see that wire lathing has been applied between the logs and it is now ready for an application of mortar.