Looks brown to me.

Seriously, it's impossible to know, and the answer is almost certainly not simple. Wood finishes typically involve multiple steps, starting with a natural product that is not the same color from tree to tree and sometimes changes color over time. Results will vary as well with the nature and sheen of the topcoat and, of course lighting. Who knows what the photographer did to manipulate the image after that.

If this piece has been colored during the finishing process it may have had a grain filler, with or without added color, one or more wood dyes, a color glaze coat over that, and a top coat that may or may not contribute much color but will affect the perception of the color.

If you want predictable uniformity, use paint.

At this resolution it's not really possible to say exactly what the wood is. The grain pattern would be consistent with cherry, maple, or many other woods.

Lenox House Design, would you recommend we have the stain custom mixed to match the alder door to the powder room?

I would have a custom stain mixed, but it doesn't necessarily have to match the door. It could be darker so it's more dynamic and works better with the wallpaper.

Even if we gave you a name like "light walnut", variations from any manufacturer, any species of wood, application method, ambient light, top coat, or any number of other factors would make that useless. The only sure way is trials and in-process adjustments like additional stain colors, glazes or toners, even with a "custom matched color."