The main panel ground is connected to a stake behind the house
Is it a hazard, possible trip or impellment ?
David
You have a couple of issues; if this is an 8’ rod all 8’ should be in contact with the ground. Second the clamp is only listed for 1 conductor, not the 2 as shown.
PS, that stake is properly called a ground rod.
Clamp/wire is installed backwards. So many things wrong. 
tom
We can probably thank the telco installer for the extra wire that is twisted around the others.
Needs to be driven all the way into the ground. Clamp installed wrong, and copper wire installed wrong on the clamp. Good catch/ find.
understand about the rod depth and acorn clamp is suitable for ground however how can you tell the clamp is reversed and wire installed wrong?
wire should be opposite of bolt.
tom
By simply looking at it. That is a real good photo.
interesting enough…there are people out there that think you can only have one ACORN connector per ground rod…ironically those are the same people that think when you have too add a second ground rod ( to meet the 25 OHMS or add the second one anyway…lol )that the GEC must be run unbroken through the first Acorn connector and then to the second one…simply not true but you would be surprised how many misunderstand that…
SO TRUE!
How often do we hear this from seasoned pros.
http://www.neccode.com/onlinetraining/page_images/1113921123_2.jpg
Typically, if I need to add a second ground rod, it’s because the inspector said so. So rather than dig around the existing one, and filing off the shroom, I run a second gec to the second rod.
Tom