Answer:
Who keeps the ocean clean?
What is put on a table cut but never eaten?
What do you call a pig that is no fun to be around?
I'll bring out your bulls and slow your roll. I may even come out of your skull.
I can be short and sometimes hot. When displayed I'm never cold. What am I?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.