Yes, it’s a larval trail in a dead tree. Not sure what kind this was, but they lay their eggs below the bark and then the juveniles eat their way through the wood and emerge from the holes as adults. Emerald ash borers are one species that does this.
scillagrace 
Is this like some kind of parasite leaving a trail in wood?? I am intrigued..
Yes, it’s a larval trail in a dead tree. Not sure what kind this was, but they lay their eggs below the bark and then the juveniles eat their way through the wood and emerge from the holes as adults. Emerald ash borers are one species that does this.
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Leaf, fabric or wood? No matter, they are elegant designs.
Wood. Yes, the labyrinthine design is quite intricate.
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I am amazed….which I guess is kinda good given the subject….
Fascinating shots Scilla.
Love’em
Thanks, Stuart. The optical illusion I got by rotating the shot was a total surprise. I was amazed, too!