Thanks everyone for your replies. Unfortunately I don't have a photo of the fruit. The last few years it did develop a fungus (which I think is called plum pocket). You can see a withered plum in the second picture. Before that though, the fruit was always good and sweet. theaceofspades: you may be right about it being planted from a pit. That sounds like something that my grandfather, whose property it was, would have done. destin_gardener: It didn't have any thorns. From my online reading, I think that yes, it is likely a Canada or American plum. It was really a hearty tree for being so far north, so I think a native tree is probably a good guess. Thanks again. And if anyone has an idea, please chime in!

I see you're new here, welcome. Pls. do some reading around here on mixes. While it's good that you're already using Cactus & Succulent mix (C&S for short), you will quickly see that many if not most of us here have learned to amend our C&S mixes (w/perlite or pumice, at least 30% or 50% to be safest), 'cause these days, commercial mixes have too much peat in them (kills out plants) &/or include wetting agents to retain water (also kills our plants). Others of us on here use mixes you'll see mentioned as Gritty Mix or variations of 5:1:1, things like that, which over time folks have learned worked well for them. Also some of these pre-made mixes contain fertilizer as well, which many of us wish to control ourselves rather than someone unfamiliar w/ our growing conditions. There are lots of opinions on mixes, but key & accepted by all of us is that to grow C&S, we need fast draining mix & what you've pictured above doesn't look like that. So that's an improvement that could be made easily & help the plants more that almost anything else one could try.

A friend found it in her yard. We live in Venice Florida. Nothing has sprouted yet. She said it has a liquid inside of it and it smells like a cucumber. I spk to a few other people and one said looks like a cactus? they are looking into it as well. Thank you, wish I could give you more info.

That photo is from 2019, and the table might be older, so it’s highly unlikely it’s still being sold anywhere. If you search ’solid gray dining table’ and other similar terms, you might see something you like. This is similar, but different base. Not available until next year, though. Try your location to see. https://www.nfm.com/signature-design-by-ashley-anibecca-dining-table-in-gray/61073771.html