I find the outter wood and smaller wood/branches give off more smoke then the big stuff or the centers...( I soak my dried wood for smoking ).
The grain and fiber of branches and the outter part of wood seems to have a less dense consistancy which takes in water better.
If the heart/center of bigger wood seems to emit more smoke it's probably because it's still holding a lot of it's sap..(which I don't find as good for cooking) it can make a food very bitter. DRY, DRY, DRY WOOD is best.....then soak it in water....LOL!
I try to use small branch type stuff for smoking...it dries out/seasons quicker ......... I have some big hickory (25"-30" diameter) almost ayear old that I haven't split up yet, and still looks way too green to burn.....prolly won't be usable till NEXT summer.
The weather is here.... wish you were beautiful
Imagine my disappointment if i were here to make you happy