Hello everyone, I'm new here and I'm a very inexperienced gardener so apologies!

There was a little tree (I think) growing right outside of my kitchen window attracting all sorts of flies and creepy crawlies so earlier, I cut it down. Could anyone tell me anything about the tree or about how best to get rid of the stump of it?

I'm not sure if I'm posting this correctly but here are some pictures: https://twitter.com/kellyluxe/status/771565449205067776

Thank you!