Probably Prunus cerasifera - a hallmark of this one is the sepals reflexing after the flower has been open for a time, something that cannot be seen one way or the other (reflexing or not reflexing) in your picture. So far I have never seen sloe in North America. I have been in Britain during the time of year it was in bloom there. It does not look like plum trees - more like a sort of deciduous Pyracantha in general aspect. Otherwise what is seen coming up around here (and where I have been in California) is orchard plum (P. domestica and other names). But by far the dominant one is P. cerasifera, as that is used as rootstock for the very frequently planted purple-leaved plums and is also able to come up from seed, on its own.

Chinaberry Caesalpinia mexicana Here is a link that might be useful: Mexican Bird of Paradise

Carolina Cherry Laurel Prunus caroliniana Thanks Kman04 I found it quite by accident while looking at a Mountain Laurel page. Kinda funny that I have been searching for the name of it for two years and just stumble upon it while asking someone.

You didn't attach any pictures.