What is this on my Green Ash tree?

[KenJax Tree]

Today i removed one of my Ash Trees due to borers and when i was looking at the other one it had these bugs all over it but they are empty shells and i don't know what it is does anyone know??

 

[ATH]

Cicada...probably dog day cicada if it is just out now. That is the shell from the nypmph that crawls up out of the ground. The adult emerges from the shell.

Forgot the link

 

[arathol]

cicada shell. Its that time of year. Nothing to worry about.