I searched the internet and could not find any references on how to identify different plum rootstocks, so I thought maybe you all could help. The posts on GardenWeb has be immensely helpful to me and it clear that a lot of you have extensive knowledge on fruit trees.

Plant A is a sucker from a Contender Peach I purchased locally. The tag says it was from The Fields of Bailey Nursery. The max height is 12 - 15 ft which I believe is standard, but it doesn't actually say standard. The leaves are large, about 5 inches long.

Plants B and C were purchased as St. Julien rootstock from Raintree, but they look different so I was wondering if one was mislabeled. Plant B forms long branches in a season with no side branches, and its leaves are more rounded. Plant C forms lots of side branches on the branches that sprouted this season, and its leaves are darker green, tend to curl, and have a tiny rounded point at the end.

Plant D is a suck from a Mount Royal Plum I purchased locally. The tag says it was from The Fields of Bailey Nursery. The max height is 8 - 12 ft so I was thinking it was a dwarf even if the tag doesn't actually say that.

Thanks for any help you all can provide.