DIY Rollup mat

[Andy in Germany]

I've heard mention of a method to make a roll up mat for gaming. I'd like to make something I can roll because of space constraints in our tiny apartment. I realise I could just get some olive green felt but I'm possibly a bit fussy about ground cover coming from a background in model railways, so if there's another alternative I'd like to try it.
Does anyone know of any methods?

[Elbows]

There are several tutorials on YouTube.  More or less it's canvas covered in a mix of paint/pva glue/tiling caulk...and then filled with grass/pebbles/sand/ballast, etc. 

[Andy in Germany]

Many thanks. I'm not sure why that didn't occur to me before to tell the truth.

By the way, the first one I looked at talks about using flock from Wood flour, which is the fine stuff produced by carpenters and cabinet makers. I suspect if you go to a high-end woodworker they'd happily let you have some of the stuff: where I used to work we'd have to take it out by the van load. Just make sure they only use solid wood though: chipboard and ply don't make good wood flour, and Chipboard in particular is held together with formaldehyde so you don't want is near you. Even beech wood and Oak are nasty in dust form so the breathing masks are a wise idea.

[Codsticker]

Check this out: major box store does wargamming terrain mat video.