Absolutely enough, if it pleases your eye. Purpose is really to keep the wood from picking up oils and dirt. One coat might reject enough, in reality. Four coats can become a full slick finish.
If you have true poplar, the above is a "plus two" proposition. First and second coats will almost completely disappear.
"Varnish" is generic - resin, oil, solvent mix. Polyurethane is one of many "resins," some naturally occurring, some not, used to make varnish.
I'am making three sets of small bookcase like shelves for my wifes
> classroom. Woking with Poplar to mach what they had made several years ago.
> Would not have been my first choice. Anyway They want a natural look so
> I'm just going to seal them. I was wondering how the wipe on poly is? If I
> put on two coats will it be a durable finish, or shoudl I brush on a few
> coats? And forgive my ignorance here, I'm a newbe to woodworking, what is
> the difference from say Poly and Varish? Thansk for the help in advance. I
> love this news group!
>