I have recently put new bark mulch in my front flower bed, and these strange yellow mushrooms (i guess they are mushrooms) have started to come up. Can anyone please help me, in identifying them and how to get rid of them? As you can see in one of the pictures, one of them is actually growing on the concrete! When i break them open, they are black and gooey on the inside. They start as a bright yellow goo type substance, and turn into a dark orange ball type thing with a hard shell on the outside. PLEASE HELP!!