If you worked on a fire crew for a couple of seasons, you ought to know about how to get started on a fire crew. The Forest Service has a certification program. You go to training, and then go out with one of the trainers and cut what they direct you to cut. It is time consuming and no way will you get to be a C faller (any diameter) the first time, unless you are already extremely experienced.
A FS certified faller is by no means a production faller. Safety is the first priority and you are cutting to get trees safely on the ground, not for maximum timber utilization. Production cutting is not to be confused with "dropping" a tree. Trees are felled in a pattern (directionally felled) in a way to make yarding or skidding logs efficient without damaging the leave trees. Production fallers have to be safe, efficient, know the specifications for logs, know how to identify rot, know how to buck a log FOR the market, and how to buck out defect--unless it is a tree length unit. Then logs are bucked on the landings. The production fallers I've been around take pride in their abilities. Most come from logging families or have friends in the business. It used to be that "kids" started out building firelines around clearcut units for burning later, but that doesn't happen anymore. The best fallers I have known, started out as kids and packed gear for their dads during their summer vacation time. That's probably against the law now.
If you just want to fall trees, and not timber, a fire crew is a good way to get going. Be patient. Don't know how it is now, but you'd start out as a "swamper" for a "sawyer" on a fire crew and maybe move up into beginning bucker. Bucking has certification requirements also. You also need to get on the ball, as training and certification starts early in the year. I think you also have missed the deadline for getting hired also. Better go talk to somebody who still works for an agency if you are by any means serious.
I was a B class bucker after becoming tired of chopping trees that were down across roads with a pulaski, and going back to the office in a foul mood where the saw certifier was very kind and allowed me to wield a saw. He said I looked comfortable running a saw and gave me a card for up to 24 inches. The joke is that after 24", one loses all knowledge of how to buck a tree up. I then went to training every year to keep the certification. I had previously worked on a thinning crew before any certification program existed.
A very good professional faller never let me forget that I was "certified" and he was not. He went in to inquire about certification and was told not enough time was available to make him a Class C faller. He wanted to cut hazard trees along his daughter's school bus route voluntarily, and was told he'd have to go through certification , and that was not going to happen. When visiting a unit he was cutting on, I'd hear, COME AND TELL ME HOW TO CUT THIS TREE. AFTERALL, YOU ARE THE CERTIFIED CUTTER. My reply was always that I'd have to lie down and look up at it as I was merely a B Bucker.
Note: This is how it worked in Region 6.