Thanks so much for the prompt, thoughtful replies, all of which are helpful. The pear tree and sucker is a real possibility, but I also may have ordered a quince a few years ago and lost track of it through the moving I've done. The advice about the drastic pruning is helpful. This tree hadn't done much because of moving it (and probably pruning a little because of the move) This year, it has at least doubled in size. My plan is to keep all three trunks, severely prune and keep the center uncluttered. I guess if I ever get fruit on all three trunks, it will let me know if the grafted pear scenario is true. If I get quince on all three trunks.......then I guess I have a quince tree!! Thanks again for the help. Ray

probably could take it all the way down.. a 'run it over with the truck' type plant ... but just pick 1/3 to 1/2 ... and cut them out ... then next year.. take those out ... no real need to make it a 3 years project ... the problem is cutting at height ... frankly.. if you cut one .. at ground.. it will be nearly the same size by next summer... if you do that at say 4 feet.. then it will be 4 feet plus another 4 feet.. and it will all flop ... that is the point with rejuvenation pruning... cutting to the ground ... ken

It depends the best time to prune is in the fall but if you don't mind a hacked bush through the summer you can prune after blooming.

considering the size of the pot.. and the size of the tree .. i think i would worry about pruning it in 3 to 5 years ... right now ... every leaf is an energy making machine.. to grow a root mass. .. to grow the tree ... and if you cut half of them off .... then its just going to take longer to grow the root mass ... get it planted.... water it properly ... yikes on that soil ... i like this primer for planting: https://sites.google.com/site/tnarboretum/Home/planting-a-tree-or-shrub do not amend the planting hole ... do you know how to water a tree?? .... do you know if you soil drains??... dig a hole and perk it ... https://duckduckgo.com/?t=ffsb&q=garden+perk+test&iax=videos&ia=videos how the soil drains will dictate how to plant it properly.. and will also aid you in figuring out how to water it properly .... tree time is counted in decades ... and getting it to live and grow a mature root mass is far more important than starting to prune it ... do you have a cultivar name????? .. seems odd someone would go to all the trouble of grafting an un named plant ... what would the point be ... ken ps: i suspect it might show you which part is which.. if you give it a season or two to grow out ... something might be obviously different over time.. like leaf structure.. flower.. etc ....