LOL first thing that popped in my mind weedI'm going to go out on a limb and say weed.
Seeing the foliage near the ground would be helpful.It does look like asparagus fluffing out.View attachment 19240 Someone from our local gardening group posted this. All I know is that it has grown 6 inches in 2 weeks. Started growing where they planted thyme and moss ground covering.