As long as I have been remodeling, and staining of trim. I have always used a 2" foam brush to apply the stain and poly. The reason dates back to the television show - The New Yankee Workshop with Norm Abram as the master craftsman. Whenever he finished a project, he always got out a foam brush and started to apply the poly or stain. So, following the craftsman, I always did the same.

I am remodeling a condo in the mountains at a ski resort and refinished all the treads on a staircase up to the loft. Previous owner had left raw oak, unfinished, and it needed to be dressed up. Now, while I had bought a half dozen foam brushes, I found a 2" wooster sash brush in the utility closet that came with the place. So, I decided, what the heck, I'll use it to stain and poly as it did not cost me anything to experiment. Wow, what a difference - stain applied smoother, poly easier to manipulate and caress to a nice finish. How did this elude me for so long? And everything cleaned up nicely with mineral spirits.

Sorry Norm, there is an easier and better way.

 

That's why I have a hard time watching those home improvement shows, especially when it comes to painting. I started painting long before foam brushes but I did try them and did not like them!

 

I was brought up applying stain with a rag and often still do it the same way. No clue why other than history....

 

I usually apply stain with a brush, occasionally by spraying but rarely with a rag although I always wipe the stain down with a rag after it's been applied.

 

I use a rag when I find a "holiday" in the stain that I missed rather than having to dirty something and clean it up just for a dot. Although, the rag takes more stain than is needed and the stain usually ends up on my hands...which need cleaning up.