That is actually plastic netting and what you are seeing is the edge of the plastic netting where it gets thick. I questioned the plastic netting, but have a freind who uses it and has been happy with it. I close the ramp/door at night so they are safe in the coop area. The netting goes up one side and down the other, the netting is 36" I ran my studs at 33" and overlapped one side as I went.
I also plan to add synthetic deck board under the 2x4 in the near future to prevent the boards from rotting near the ground, I did not use any treated wood on the build.
The electric wire that I need to get ran around it is just to insure that coons and other critters don't tear up the netting. From what a freind said after they touch the wire a couple of times they just stay away, I have had them in there for atleast a week now though and have not had any sighns of an attempted break in.
We have also trapped and relocated every coon that we could as precation and have not seen but 1 in several months.