A couple of companies manufacture snow products which basically incorporate a resin, plaster and some pigments which you mix into a paste.
I was actually looking at a snow set today but it looked a bit pricey and you could come up with the same yourself by mixing the three products above.
One such supplier of the pigments and resin is MIG Productions, but there are others.
As for bases I have seen just about anything used but a couple of things that may be of interest are:
1) Shredded green kitchen scouring pads used for grass and brush
2) I have used a number of times for vehicle diorama's wet and dry sheets glued to a base to represent tarmac, you can create skid marks easily on the surface by dragging charcoal across it.
3) Another road surface I once made was a cobbled street by using modelling clay (Das) and cutting it into slices, then strips, then bricks and rounding them off before setting them on a baseboard. It made a very realistic cobbled surface. |