Snow is white—which is really just to say, it is the same colour as the light source.
But, white on a tree does not require snow—frost is white; so is rime. We have had extensive rime on mountain slopes of late.
First some snow: ice crystals that form in clouds far above the surface and then fall only to pile up on the ground and trees. This picture was taken Sunday morning after a heavy wet snow began bringing down the odd tree.
This shows rime on the trees (well, maybe also a bit of frost). The cloud contains supercooled water drops which collide with trees, freeze on contact, and coat the trees with ice—the rime.
A characteristic of rime is that it only coats those things that are imbedded in the cloud, or fog. The rime coating the trees in a band was caused by a thin cloud against the mountain. Snow can be seen through the clearings.
Being white, snow has the colour of the light source: lit primarily by the setting Sun, it appears pinkish; lit only by the darkening sky, it appears blueish.
Rime is sublime.