This maple floor turned out beautifully!
We usually avoid staining maple floors simply because they rarely turn out looking good. The grain characteristics of maple make do not take stain well without being blotchy. Maple has a great deal of variation from soft grain that absorbs a lot of stain to hard grain that barely absorbs any. This makes it nearly impossible to get an even distribution of stain across an entire floor.
But just this week we did a maple re-sand and stained it dark. And it turned out beautifully! We had to take extra steps to even out the stain, and it was very time-consuming. But the floor looked so incredible, the first thing the homeowner did was take photos of it to send to people he knew. He was stunned at how well it turned out. So was I.
Normally we recommend if you want a dark stain on your floor to go with white oak because it takes stain the best, without the wood adding much color to it like red oak would. But in this case, the floor was pre-existing, and the homeowners had a light stain on their maple that they were not happy with.
So, keep in mind, if you are thinking about going with a stain, the species of wood you use can make a huge difference in the outcome of how that stain will look.