Usual practice here in wheat/barley country is for the combine to cut and thresh the grain. The straw is put out the back of the machine into 'straw spreaders', just a couple of big whirling blades that spread it out behind the machine. If the straw is to be baled later, the straw spreaders may be removed to leave a swath of straw or if they are not removed then a side delivery rake puts it into swaths for the baler.
Plastic twine is a real problem. It doesn't deteriorate and thus lays where you drop it for years. People who run sheep do not want to use it as it gets in the wool and renders it unsaleable. _Most_ people using twine tied bales are careful to retrieve the stuff and dispose of it properly but I had a neighbor that just let it drop and lay there. His barnyard was pretty much of a 'yellow lawn' from all the ends stickign out of the mud. I also recently hit a piece at another farm with my chainsaw which promptly wound up in a big, snarled ball around the drive sprocket and in the chain. Didn't even try to clear it until I got home.
Harry K