Wood 2

Wood 3

Hmmm. Looks like it could be a pine. It's not oak. If it's something unusual it could be hard to determine. Is there a chance that the builder could have used unusual wood like pecan?

Based on the photos, my best guess is maple. The dark parts are heartwood, lighter parts sapwood. It would be a common flooring material because of its density. Second choice would be birch that has a similar grain pattern and is likewise diffuse porous.

Probably soft maple.
Casey

First glance. I thought old growth Poplar like I am am using on the walls of a partition in a basement to hide the flex duct work in a house I bought.

The wood you have is to light and the wrong grain for old growth Poplar.

My guess would be Hemlock, Spruce or Fir.

You didn't give an age of the house but I would say old growth fir. My 1890 house had floors like that.

i think your best bet would be to forget the name of the wood. buy the flooring that is closest and stain to match. most likely, whatever your wood is, it's currently not being produced for flooring.

I would say fir

I'm not sure what it is, but I've worked with fir for many years, and that does not appear to look like any fir I've seen, either in grain pattern or how it takes stain.

Fir has more of a 'piney' grain pattern that is more coarse and defined. Your wood has a very fine grain pattern. It's reminiscent of pine in a few places but overall it does not say pine or fir to me.

Do a google image search for "Chestnut lumber". There is wormy chestnut that is the spittin' image of what you have there. Chestnut was used back in the day but is not found much anymore. It would be consistent with an old house though. Very beautiful wood!

Looks like reclaimed Cherry to me......

The stair treads are BIRCH. birch and maple especially that old can look very similar. some tip is sand a little bit, if you get a sweet sugary smell, its maple, otherwise its birch 100%