What’s Halloween without a little fun-gi. Arguably the most creepy of all fungi, Xylaria polymorpha can look like decaying zombie fingers creeping up from the forest floor. Commonly called dead man’s finger fungus, it and other similar sinister-looking fungi in the genus Xylaria grow throughout the United States.  Take a look at at nine creepy pictures of this fungus—if you dare. Dead man’s fingers are usually spotted at the bottom of decaying or dead trees. They break down deceased wood and release nutrients into the soil so that new plants can grow. Image: NPS/Bradburn. The finger-like shapes themselves are the fungi’s sexual reproductive structures. Image: Khlongwangchao via Getty Images. Like a real human finger, their exteriors can be rather stiff and strong. That firmness helps them to release spores and increase their chances of reproducing. Image: NPS Wheeler. Xylaria are incredibly opportunistic genus and can release these spores for several months or even years. Image: NPS/Stiteler. The mushrooms grow from the forest floor among dry autumn oak leaves, with a mossy tree background in soft focus. Image: grechanyk via Getty Images. Simply plucking a dead man’s finger from the base of a tree doesn’t get rid of the fungi itself. It is merely the tip of a much larger organism.  Image: NPS. The creepy fungus is found on six continents. Image: Dr. John A Horsfall via Getty Images. Some species of  Xylaria are known to cause black root rot, but that is typically a problem on trees or shrubs that were stressed already. Image: Riski Wayuningsih via Getty Images. Don’t worry. It’s completely harmless to humans, despite its walking dead-like appearance. Image: imageBROKER/Frank Leo via Getty Images. The post 9 spooky photos of dead man’s finger fungus appeared first on Popular Science. ...read more read less