Joss an 11 month member of my online Model Train Club has posted this idea at the club.

I know you can buy ready-made ground cover, but I’m a bit old fashioned and like to make my own. I gather up dead leaves and crush them in a kitchen blender. I then gently bake the moisture out, or I thoroughly air dry the mixture (don’t start a fire in the oven!). I then use a sieve to sift the baked material to look like tiny fragments of dead leaves (which is what it really is). Apply some ground goop to your surface area and sift on the leaves to bond them to your forest floor. Leave it to dry. I haven’t had any problems with the leaves showing any signs of decay or mold, and I first used this method a few years ago.