I live in Allison, Iowa and I found this weird yellow and fuzzy cocoon thing! I am not sure what it is!?

I think it could be a spider sack or a caterpillar cocoon but i dont know and I am curious to find out! Pleasse help me figure out what it is cuz i am going to keep it and see what it turns into but I would like to know ahead of time before it hatches so I know what to feed it and stuff when it does open out of its cocoon thing! Please help me!