"We have never fertilized our trees and would like to start. "

Why?
What leads you to believe that they are suffering from a deficiency?

If that pH report is from your soil test I might spend some time trying to lower it.
If it is just local "common knowledge" I would get a soil test to find out for sure.

At most I would toss a bit of Holly Tone around- more than that is not necessary.

Have to agree with the above......woody plants (trees and shrubs) established in the landscape generally do not need fertilizing unless they show signs of obvious deficiencies. Even then, it may be more a condition related to pH than it is to lack of nutrients, as an inproper pH can limit nutrient availability. All the JM's would be happier in more acidic soil, so I might attempt to lower pH.

Other than that, I'd be inclined to just let things be, especially if "all the trees do great in the spring and summer" :-)

Where did you get Mexican Sugar Maple? It's not widely available. Heck, I only know of one place that sells it is at SFA plant sale that I bought one last week. I did grow one from seed but due to lack of space at the old house in Dallas area, I gave one to my neighbor. I wonder how it did this year. I collected a lot of seeds last week. Should be fun!

I've grown Fire Dragon and it's the toughest one of all maples you've listed. I had one that was 18 ft tall and 15 ft wide. Doesn't look like Mexican Sugar Maple likes alkaline soil too much. How long as it been in the ground?