Portable scenery idea.

I would go with Modular type construction.

I would make all buildings removable so the module height is low for putting on a top.

Then just make a shallow box as a top for each module to screw/bolt on for transport.

These can be stacked easily and protect your work.

They can also be stood on edge for a time if the scenery is well secured.

Buildings of similar height can be boxed together with some padding.

I would suggest you use masonite sheets, cut to any shape you desire, screwed down at the corners and/or toward the middle of each outer long edge to prevent warping. Glue eveything to the masonite, and you will have no loss whatsoever. If you don't want to glue the buildings down (for inserting lighting, later, for example,) that's fine, too.

Here is a wide variety of examples of how I use the method I just explanied...

Those are great suggestions, and awesome detail work by the way. Today I layed down some paperback grass mat, ths will be the base for a farm kit Im working on. Since Im thinking of building a small downtown area the masonite sheet idea will work very well. I picked up this months issue of O gauge and if you guys havent seen the "Destination Peedyville" article you should, it made me realize I need to learn to make my scenery work a little more organic and natural. 

I understand your desire for portability, but "rolling up" ground cover and foliage, IMO, will result in loss of the ground cover and foliage damage in the process.

I agree that modular is the way to go.  If you don't want to go quite as far as Monsoon's approach (just ground cover and foliage w/o any buildings, vehicles, people, etc.) you might think about storing your ground cover modules in a vertical, wheeled stack cabinet such as may be found at any office supply store or Ikea.  They come in a fairly wide variety of widths, heights, and depths, and are relatively inexpensive.  And they offer a good storage system for all of the miscellaneous stuff one accumulates in building and operating a layout, too.

Poppyl   

I built mine all modular. Used the masonite approach and blue styrofoam for scenery. All track has joints at each end of 2'x8' section.Large Styrofoam mountain comes apart in four sections.

My entire 5x8 table layout is filled with "scenic modules". It stated out as short-pile muted green carpet covering with FasTrack on it. Now, only 5% of the carpeting is visible, and that's hard to spot since the color blends well with the scenics. The process took 2 years to complete. The layout is supported by 4 saw-horses. When/if it becomes time to move it, nothing will have to be destroyed...just box it up.

My round-the-room layout is small but with hard to reach areas for a lame old o-gauger. I now follow the practice of Velcro-ing everything---scenery and structures for removal to work on them as well as Masonite backdrop panels that may be removed for painting or photo murals. The corner photo below shows a work-in-process that is 60" diagonally from the layout edge and quite a "reach". The 3 piece mountain, the portal, sawdust pile, mill and shed are "spot" Velcro-ed and easily removal for additional needed work. The 13" H. x 8' L. masonite backdrop panels are attached with Industrial Velcro and can be removed to place on easels for painting,mural,etc. When I ever get around to populating my Village area with structures and stuff and folks, Frank's modular-on-Masonite practice will be swiped and used. 

Speakin of "swiping," Id like to swipe that beautiful lumber shed you've crafted there, Dewey. It's really very sharp.

Frank

Thanks for all the advice guys. I wound up designing the layout around 1x4/2x4ft bases( easy size to fit into my car leaving home depot and large enough to minimize seems). I apologize for the terrible cell phone pics. The open area in the center is going to be a downtown area built on one solid 2x4ft mdf base. After its done it should drop right in...much easier than attepting to bend over the raised outside. Thanks for the great ideas everyone!