There are hundreds of flash in the pan carpenters, welders, (insert whichever trade your jacklegged ass can't make it in here) treeman wannabe startups coming into the trade everyday. As has been mentioned, you will lowball and screw up every tree you can reach with you ladder, polesaw, bucket truck, give the trade a black eye and screw up the market in your area for the few months/year that you last until you can finagle someone else into hiring your jacklegged ass into whatever trade you are not making it in in the first place.
Let's see, I did a little gas and arc welding at votech in high school... I think I'll start a fabrication business... Yeah, that's the ticket.