I'm writing a story that will have two people forced to spend the winter (late November to mid-February) in the middle of a forest (Alberta, Canada). They'll have food but it'll be mostly bread (they have flour + yeast), dry meat and potatoes or beans (whichever turns out to have a better balance weight-nutrients-store life). I wanted the characters to collect plant foodstuff to enrich their diet.
According to this website, the ground in the Edmonton area can have an accumulation of snow from 1cm (0.4 inches) to an average of 18cm (11.3 inches). Common sense dictates that the deeper the snow, the harder it will be to collect plant foodstuff, however, in the best case scenario (snow 1cm deep), would it be feasible to collect roots (like broadleaf cattail rhizomes or wild onion) or rose hips (since, not being roots, would be more visible, if they exist)?