The key difference between Fragaria vesca and Fragaria virginica seems to be the terminal teeth of the leaves. I assume the subspecies of F. virginica will still follow the same pattern. I can vaguely tell the difference from photo IDs but I don’t have a key for them.
On F. virginica, the apical tooth is shorter than the adjacent teeth.
On F. vesca, the apical tooth is the same/longer than the adjacent teeth.
I hope that helps, if I’m right! Key used, from this site: https://gobotany.nativeplanttrust.org/dkey/fragaria/
Also, you can find AMAZING plants on the side of the road! Give them the benefit of the doubt :) This is just my opinion, but you can dig up one plant IF the population there seems to be sustained. Though, if you can revisit-- it’s better to collect seeds both for the population’s sake and genetic diversity.
My roadside patch is always mowed before anything can ever seed. So, I find it better to let them overwinter in my yard. For their sake, obviously.