Fun fact: You can grow maple trees indoors and they will grow to the size of their container. You can keep small mini trees in your home.
@RadioAngel How big do they have to be to reliably tap?
@socalledunitedstates I'm not sure. This is definitely something I want to find out about though. Generally I think it needs to be a well established tree. You can get a few liters in the fall without harming them.
@socalledunitedstates I know my maple tree in my front yard is about 8-9ft tall and could be tapped easily.