I also have some of those little white flowered begonias running loose around here. They're pretty well behaved and are in only a few areas. I just run the lawn mower over them.
They look very much like the one I grew in my living room back in Ak., except that this one is not as red as the other.
Got a "bunch" of Oncid and Catt inter-generics recently opened and getting ready to open.
When this flush of orchids are all open I'll post pics in another thread.