Here is another picture of the residue after I wiped with a paper towel

No pic of the actual damage is attached.

Hopefully, you have called a termite exterminator.

Here's a hint (as in...get in an exterminator ASAP). Termites start at GROUND LEVEL and move UP into the home. Actually, they can even start BELOW ground level and move UP into the house. They can and will go ALL THE WAY UP to the rafters if they are left to do what they want.

The visible damage you see is only the tip of the iceberg. All the damage (90%-99%) is out of site. Which means you have no time to lose because they have been going at this for SOME TIME.

Where do you live? Certain parts of the globe have certain species of termites. Each one has it's own speed at which they can demolish a wooden home.

I live in the San Francisco bay area at Saratoga.

here is another picture of the floor

Get an exterminator in pronto.

California has a strong history of termites. Termites LOVE warm climates....LOVE THEM! Have you ever seen the termite mounds in Africa?? They can be 2 stories high!

Termites START in the ground and CHEW their way UP. If you are seeing damage/indications ON your floors it means the WOOD BELOW has been infiltrated already.

You need FULL TERMITE REMEDIATION. That means PROFESSIONAL help = RIGHT NOW.

There is no DIY topical spray that can deal with this. You can try....anything you want...but it won't keep your house from falling down.

Yes. We have seen it. It is very upsetting for homeowners. And homeowner insurance doesn't cover it.

I’m not an expert in termite problems, so I’m curious to know if this is absolutely termite damage or if it could be another type of bug.

It does seem like a termite. But not as extensive as i thought. But i have professionals scheduled to come in a day or so. I am also thinking of using the spray on the surface tonight. I actually mopped the whole surface yesterday with vinegar and hot water. Since then the infestation went down considerably. Today morning I went to check and saw just a small bit of termites come back and just around the edge of the floor. So they are still there but perhaps dyeing. And I don't see anything else visible in the house. This room is on ground floor and there is no crawl space there. Attaching the picture from today morning. I mopped it again and cleaned it out.

Here's the old termite damage in my house that got fixed when we re-sided. The guys fixing it brushed away the damaged wood with a gloved hand. I don't see anything like this in your pictures.

Its hard to tell from what your pictures showed, but, if it is termites, your vinegar stuff is not going to get rid of them. It may keep them from coming up on that flooring, but, they will just move to a new location. I would leave it all, and do no more until the professional comes in and inspects, so he or she can determine just what you have and how it should be treated. If it is termites, damage to the hardwood floor is the least of your worries, they may have damaged structure already and are now moving into the hardwood.

Termites live individual lives. The forage for themselves and by themselves. As soon as they detect poison/noxious stuff they seal off the tubes and start again.

Don't think you've done anything other than moved them behind the walls.