Ah, come on Treelore, I would bet that treeseer would have a plan to save that tree.
All kidding aside, find a better tree to learn and practice in. From reading your other posts it is apparent that you have made your mind up to do this work, at least on a part time basis. At the risk of being repetitive, find someone who has been in the industry for years, and work with, or for them. They will be your mentor, watch what and how they do everything, and keep an open mind.
Have your spouse put a lock-down on your wallet and credit cards, I think your are wasting a lot of money on stuff that will litter your garage, once you become acclimated to the industry.
My hat is off to you for starting this undertaking at the age of 61, I really hope you take the advice of others here so you live until your 62. One of the best guys I have ever had working for me was in his 60s, he had a fantastic work ethic, and appreciated the opportunity to work outdoors.