I have no experience with grafting and plastic bags but to be on the safe side, what one does with seedlings, rose cuttings, etc. that have been in a high humidity environment like that is to open the bag for a short while each day and then gradually lengthen the amount of time the bag is open until you can remove it entirely. You follow a similar pattern when first putting the plant/tree outdoors from indoors, put it out in a shady spot for a short while, lengthen the time outdoors, and do the same for sun exposure. If you were to plant it in the earth, cover it with a burlap bag and cut a new hole in it every day or two until the tree acclimated to full sun exposure (remove the lacy bag). Good luck.

Greenwich,
Before reading your post I had decided to remove just the two plastic bags covering the grafted scions and have been misting them with fresh water twice a day. In the evening I am placing the bags back over the two scions but I am not securing the around the bottoms. The other two scions are starting to show some small green color just on the very tips of the buds on them
When trying to grow limbs do I follow the same rule and just use one or two buds like one would graft a scion on to rootstock? Should I remove anything on the scion with more than two buds? That has me puzzled because I am trying in this case to grow limbs and not the main trunk of a new tree.
Photos below you can see the open buds without the bags obstruction the view.. Thanks for your advice.

Lou NE., PA
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