Round up effects

Every year we plow up ground to plant oats to graze through out winter and into spring. This year our grass is so tall our tandem disk would never even get to the dirt. I'm thinking about shredding it and then burning it down with round up to make it easier to disk. It's all Bahia grass so I'm not worried about hurting the warm season grass stand. Just worried if this will effect my oats stand?
Thanks

Round up effects