Looks like the Acer ginnala I picked up from the nursery for $10 over the winter made it! It was frozen solid in ice when I bought it.
Should I start chopping? If so, what would you cut?
Also is it worth repotting into a training pot with substrate or leave it in the nursery can to develop? Not sure how much I can do at once this season in zone 5.
Buy more trees, and let this one be for a few years. :D
Aaron, you may need to see if there is better nebari further down in the future. For now, after the severe work you should let it grow and let the new shoots run out quite long to allow them to thicken.
I agree with Dan's approach. I have a ginella maple that I bought half off at a nursery last year. I think the first thing to do prior to cutting branches is to get down to the true nebari in the nursery can. You will likely find good basal flare and the best root spread will determine the front of the tree. So prior to cutting, I always identify the root spread, as it will inform my pruning decisions. Ryan Neil has a great piece of content on working nursery stock on his Mirai live platform.
You have to get down to the true basal flare and remove any roots growing upward, across etc. Here's what the base of my maple looks like after the operation last year. I reduced the bottom of the rootmass also, but you don't have to at this stage. Hope that helps!
It's hard to give you direction on style options with the photo's, but here's what I would do if it was mine. (This is assuming all looks healthy and the buds begin swelling.)
Every single amur maple I've had has ended up having a much larger/better base under the soil surface, so I'd be willing to bet that you've got something more going on beneath the soil line. You could: A. re-pot to organize the roots and find the true base of the tree, or B. you could start scraping away the soil and cutting down the container until you uncover that base if you're not comfortable re-potting this spring.
I would also find the line (trunk movement) that you find the most interesting and cut the tree back to that. I'm guessing from the photo's that one of the main lines will need to be either fully removed or at least severely cut back. (Start with cutting off all of the dead twigs so that you know what you're working with.)
You can get away with the cut back and root work at the same time in a young vigorous deciduous tree, but there's also no need to be in a rush. Personally I would likely do a bit of probing on the base (option B above) and cut back the trunk to the desired line this year. Let it grow strong this year and then re-pot with serious root work next spring assuming it grows strong after the work this year.
Hope this helps! And there may be others on here with experience different than mine. I'm excited to hear what everyone has to offer. :)
The answer depends on what you want to do with the tree? What size pot is your tree in? How big is the trunk in inches right now? If you want a bigger tree, then stick the whole pot/tree into a gravel bunker and grow it out. The one long bigger straight trunk should probably be removed but not until your done growing out the trunk if you want a bigger tree. Maple trees in general are not chopped until after the first set of leaves have hardened off. Here are three articles you can read and study, both are very good: For Beginners: Trunk Chopping 101 For Deciduous Trees , Working the Trunk and Maple Trunk Chopping. You can also find more information on this subject here: https://rockymtnbonsai.com/index.php/bonsai-basics/chopping-trees/
Some more information would be helpful. How about some photos to start with.