Dog Vomit Fungus

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Several years ago, more than I want to remember, when I was working on a lawn in the Chicago suburban area, I was walking close to a house and saw something very unusual in the landscape bed that was covered in mulch. At first, I thought a child had been playing in the area, became ill, and vomited in the spot. I didn't think much about it at first, but each time I walked by the spot, I became more intrigued with what I was looking at in this mulch bed. I am not an expert on what a pile of vomit looks like, but I noticed that what I saw did not resemble any vomit I had ever seen before. It was bright yellow and smooth across the top, with what looked like bubbles that had risen to the top and popped.  Being the curious type, I found a stick and poked at it. It was very gelatinous and somewhat frothy. I had no idea what it was, but I did know that it was not the result of someone being sick. I figured it had to be some type of mold or fungus that was growing out of the mulch. This occurred  well before the era of the Internet, so I had to research it the old fashioned way, looking at some reference books.  Lo and behold, I found my answer—it  was called dog vomit fungus. Dog vomit fungus is not a fungus; it is slime mold, also commonly referred to as dog vomit slime mold. It usually forms on mulch in late spring to early summer following extended periods of rain. Initially, it begins as a bright yellow, gelatinous growth, emanating from spores that were in the mulch. As it matures, it hardens, fades in color and becomes less noticeable. Finally, it dries out completely and decomposes, but leaves behind millions of spores that can be carried away on the wind to grow again another day. There is no control for dog vomit fungus and it does not really need to be controlled. It usually goes away on its own in a couple of weeks. If you see it in your landscape bed, take a picture of it and show the weird slime mold to your friends and co-workers, who may be fascinated or repulsed.