It's most likely an algae, especially since it's green.
There are slime molds but I have never seen or heard of one that
You might want to be more specific about where you live.
In the woods doesn't really tell the real experts here much.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.