Yes, resin: I read this topic (over in the trees forum) too fast--I thought these trees were in the Pacific NW. Ugh, I had a senior moment. You are right--I have seen almost nothing but sick Douglas fir around here. They seem to do OK for a while, but as they age they almost always get some kind of disease that I have not identified, and go downhill very fast. They are also sometimes devistated by sap suckers. In spite of my love for these trees, I will not plant one here. But there is one absolutely beautiful older one I know of. It is on the grounds of the Oatlands Plantation house south of Leesburg, VA. This tree is stunning--about 70 feet tall and as full and lush as one could wish any conifer to be. But Douglas fir is very variable, coming from a lot of different kinds of climates in the American West. Whatever the provenance of this tree is, it should be determined and published for all who want a tree of this remarkable species here in the "mid Atlantic" states. In any case, all this does not tell me that some lawn chemicals might not have hastened the onset of decline/death of these trees. --Spruce

I think you need to strip the stairs down to bare wood and then compare some samples of the flooring stains to to get a close match with the 2 different woods. You need to find a good flooring finisher not your contractor.

I might try this three step process using Minwax Simply White 275, Fruitwood, and Early American. Wiping off between applications. See blog post: https://www.lilyardor.com/how-to-stain-wood/#:~:text=For%20my%20stain%20I%20went,are%20by%20far%20my%20favorite.

I can't help with the woodworking, but wondering why you think they need to match? Since framing that has traditionally most often has used a different wood than floors, they seldom matched. Perhaps a stain that would coordinate with the flooring could work for you? You didn't mention what color you're staining the oak floors. You can use other wood pieces in the room to bring the 2 colors together.