Answer:
Nothing specific, but more than a few. This many clustered, together will do.
What goes up and down without moving?
What is red and smells like blue paint?
It can be clear like water, but it burns like fire.
What should you do when you see a green man?
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.