Good Afternoon Michael! 

Sounds like a lot of good little trees - you'll have a beautiful stand of red maples in no time! As for your questions - 

I would do as little transplanting as possible. The best times to transplant them are early spring, and late fall (after leaf drop). Basically we want to hit them in their dormancy. We want to avoid putting them through the stress of transplant shock twice, so I wouldn't up-pot them, rather put them directly into their permanent home. 

It sounds like they have already begun to bud and leaf out - were they stored indoors or outdoors? I would say we've missed the early spring date because the trees sound like they are no longer dormant. I would advise planting in late fall for that reason, directly where you wish to permanently have them growing. If they are stored inside, I would slowly introduce them to their future homes a little at a time. This will get them used to wind and strong sun slowly so as not to shock them before they are even transplanted.

When planting, you will want to consider the location - soil tests through UVM extension can give you further info about the soil properties where you want to plant them, and will help you to figure out any amendments you may want to add to the soil. A lot of resources also advise marking the tree to replant with the sides facing the way they were originally (South facing, north facing, etc) but if you have already potted them and removed them from where they were I assume this is not possible now.  

Red Maples (ACER RUBRUM) prefer partial to full sun, and are prone to damage and sensitive to injury. So Gentle is the way to go. When you transplant, the hole should be 3x the width of the root ball and about the same depth. Mix any amendments in with the soil after digging the hole but before putting the tree in the hole so that it is mixed thoroughly with the natural soil. After transplanting, water frequently until winter. 

For trees this young, I would recommend using two posts on either side of the sapling and lightly tie them to the main trunk to keep it stable and upright until it is well established, and you can wrap a mesh around it that is strong enough with small enough holes to prevent critters from getting in and eating at it, but large enough holes to allow for sunlight to filter through. Not sure how tall your saplings are but at this point I would make the protector as high as the tree. Once winter sets in, you can stuff leaves and straw into the tube and cover to overwinter. 

Hope this helps, and let me know if you have any further questions - Happy gardening!

Kristin

https://ehq-production-us-california.s3.us-west-1.amazonaws.com/c3fb91d5f7c729647a33fedea6548fbcd39878a2/documents/attachments/000/003/023/original/VT_Tree_Species_Selection.pdf?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIA4KKNQAKIJHZMYNPA%2F20250430%2Fus-west-1%2Fs3%2Faws4_request&X-Amz-Date=20250430T165610Z&X-Amz-Expires=300&X-Amz-SignedHeaders=host&X-Amz-Signature=3f274430f56b292a1baaf1466a6e65b49f50abf3c41cacee94d8ecae1be68e4d

https://extension.umn.edu/trees-and-shrubs/red-maple

https://extensiongardener.ces.ncsu.edu/2023/11/transplanting-trees-from-the-woods/

https://extension.umn.edu/how/planting-and-transplanting-trees-and-shrubs

Hi Michael - 

That first link somehow did not come out right, please see corrected link here: https://vtcommunityforestry.org/sites/default/files/2022-11/complete-vt-tree-selection-guide-2022.pdf

Also, you might find the UVM soil lab info helpful here (for the purpose of monitoring and testing your soil): https://www.uvm.edu/extension/agricultural-and-environmental-testing-lab