@James
I have some experience with using sprues to create terrain, my personal favourite is to use them for bricks, i have some cherubs based with sprue bricks, Bugmansson's table and wood flooring is also made from sprue, as seen below.
For wood i would say remember that it splinters and has crevices, these can be simulated by a knife stabbing and scoring along the sprue. For more info on how to do this, i would recommend looking at GW printed wooden planks and they will tell you how it looks like, maybe some pitting as well to simulate knots could be cool, but im not sure how to do that myself.
Also, Castle Spruestein is a worthy mention of an entire project made from sprues, although i wouldnt recommend it, it was long, sometimes getting high from the super glue, and very messy!