I am getting back into gardening after a long hiatus, and I was never an
expert at it in the first place.

I have three varieties of tomatoes down in a small garden. I read in
William Woys Weaver's book on heirloom vegetables that Brandywines should
be isolated from other varieties by at least 50 feet, in other that they
"breed true."

They are not that far, not even close. I am wondering if I can expect
whatever I find on the Brandywine plants to be crosses with the other
varieties in the garden. I have Rutgers and some cherry tomatoes. The
cherries look as if they'll set flowers and produce first.

Does anybody know what will happen in this situation?