I'd follow the wire of the phone to a random house and order some pizza using my phone. Then I'd run to the nearest convienence store and buy a map so I could figure out my way home.
2nd way (if the phone was a cell phone)
I'd order some pizza and tell the delivery guy where I was. He would laugh and hang up. After that (out of pure frustration) I would have chopped down every tree in the forest for days while eating the fallen gumdrops from bushes and trees.
Then I would have find my way out because there wouldn't be a tree in sight.
3rd way (it doesn't any more stupider than this)
I'd get some bug spray and some matches, spray the can of bug spray on every single tree around me, and then light the bug spray with the matches. Since the bug spray is flammable, it will create a forest fire (or jungle fire) and clear the whole jungle. Then I'd hike out of there