Be careful as this type of work can quickly become addictive :;:smokin.
With you only wanting to plant a dozen or so trees, you should be able to hopefully take care of them by spraying, mulching and caging them - which will result in them having a better chance of survival and also growing much, much faster. I've been doing more of the carpet-bombing approach where you order 100 plugs, stick them in the sod, and hope for the best - figure maybe will end up with 50% survival if lucky, but can't take care of that many trees so they gotta be tough
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Trees planted in sod take FOREVER to get going as they struggle to survive the first couple years, but I think they will eventually take off. This is with Eastern Red Cedar trees - which are about the toughest tree around.
Bare root trees from the soil conservation district get tubed for a year, sprayed, and mulched - then they need to be on their own, but these are brush trees which should be able to take some browsing. Apple trees need cages for life.
Good luck and keep at it - nothing better than seeing a tree you planted providing some food/cover for animals you appreciate.