Ok, here is my submission. I'll add in more pics when I get a chance to take them. Work has taken so much of my time lately that I am mentally drained and just haven't had the opportunity to put as much into things lately.
Here is what I did for this - fortunately I did not need to "make" much stuff for it, I am thinking that as much as we can avoid making, but still making things affordable, it will help.
1.) - I bought a piece of subfloor (like a large sheet of foamcore, but is wood) from Home Depot, the smallest sheet I could get was about 3 feet x 4 feet. For what I wanted to do, I wanted to scale it down to 2 feet x 3 feet so it could fit on the shelf I put it on. The board was 1/4 of an inch thick. I went with that instead of the 1/8 inch to avoid warping.
2.) - Then, I measured out the frame I needed for it to be. Once it was measured out, I made lines with a pencil where I needed to cut. I cut it with a heavy duty utility knife. Took me about 10 minutes to get it cut.
3.) - After that, I had a roll of Woodland Scenics ready mat that I had purchased from a hobby store for $25.00. The ready mat measures 50 inches by 100 inches, so it's huge and you get a lot for your money. It is meant to resemble grass/tundra.
4.) - After cutting the ready mat to fit onto the board, I had some styrofoam glue spray - this is a spray that you get at hobby stores made to bond styrofoam together for craft projects - it worked PERFECT for sealing the mat onto the board. Took less than a minute to get it how I wanted it.
5.) - Once the mat was secured onto the board, I flipped it upside down and traced around it using the utility knife to cut off any excess mat that I did not want.
6.) - At that point, I used a bit of spray paint here and there just to add different color texture to the mat.
7.) - The mountain background is from Michael's - it's not cheap but it really looks cool. I have bought several of them in the past and spray painted this one to give it more of a hard stone appearance. My mountain technique is not the cheap way to make them at all, but they do look good I think.
8.) - The Gun Tower is something I purchased from my friend Owen D. at www.owenscustoms.com
a while back, just added it for variety
9.) - The shrubs are just cheap lichen you can get at Michael's. It's cheap and easy to use.
10) - The grassy plant is from Michael's too - they have TONS of little plants like this for pretty cheap, and so does Hobby Lobby. Might be worth getting stuff like that for cheap instead of trying to make so many of our own plants.
11) - The trees are from Kmart - Christmas scene trees actually - they had snow on them but I just repainted them to get rid of the snow.
I will take more pics of this with different angles, with figures in it. But I really wanted to show how the ready mat looked - I love it. It may not appear to look much like grass in the pic, but in person it does look more like it, and with cheap shrubbery we can flesh out the diorama wilderness rather easily I think. Plus with just 2 ready mats - we can cover an area of about 8 feet x 16 feet VERY easily and it will allow for the ground terrain to have a consistent look to it. Plus if we have a large board, a team of 3-4 people on site can probably have the main base of the terrain put together in an hour of less. To me that makes so much more sense than people trying to make a ground in several locations, ship it, and try to piece it together. For terrain like caves, trees, etc - that's a great idea. But to actually make the "ground" like that... I think that would be a terrible mistake.
Plus, there is a way to add in hills with it too, we would need a heat gun to do it but apparently it works well and is simple to do.