Do not use a Rotary combine if you plan on baling the straw.  It's about like trying to bale sawdust..

That aside,, as has been said, bale with as much dew as possible it might hold together a bit better.

I baled behind a rotary exactly 1 time, never again. What finally made it into the bale wasn't worth the cost of the plastic twine.  Had the custom harvester do a field and I had told him right at the very start, "don't spread the straw, drop it in the windrow, cause I'm going to bale the straw".  Even knowing that I guess he didn't feel it too important to send one of his other combines in to harvest the field,, and sent his rotary instead. I was led to believe one of his cylinder machines would be doing the combining.

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