If your soil is really bad you might let the callery grow an extra year or two after you transplant them. Some states dont allow additional callery to be planted but 50% or more of the rootstocks under fruiting pears are likely callery. BET trees are very good as well. This is a good thread to review on grafting them over later
Today is September 3rd and the trees look great. Would love to prune but fireblight was bad this year so im avoiding pruning until the weather gets colder. These trees are close together since the soil is very poor in this location. Do you believe this soil would not grow grass when i came here. The spot was bare for years until i dug it out and put chicken house manure and hay in the spot multiple times. Each time i added weeds or manure the soil got better. Never went over 3 and a half feet deep because literally a pick was needed just to do that. Eventually the location could grow rye then tomatoes and now can grow fruit trees.