In the winter forest

A woodland rhizome, either Solomon's plume (Smilacina racemosa) or Solomon's seal (Polygonatum sp.). 

Duff and snow cover protects woodland plants' seeds and roots from super-heating in direct winter sunlight. I'm sure you've noticed the sun is very warming, even on the coldest days. At sunset, temperatures decline quickly, so a plant may experience temperature shifts of 10, 20 or 30 degrees in just one day. Friday's winds rapidly dried up the roads and sidewalks - it is no different in the forest. Again, snow cover protects, this time from desiccation. 

Many forests I've visited in NJ lack a duff layer because of invasive earthworms - most earthworms are not native to the Northeastern forest. The above forest lacks a duff layer, as well. We've had a rather warm winter, no snow, just rain. Our forest is without a down jacket. 

A tulip tree, the main trunk was tipped over and resprouted