Very large canvas sheets that can be rolled up and easily transported.
Event sponsers logos are laser cut out of the fabric, with the large spaces done in a fine strip pattern to maintain the structural integrity of the stencil.
Several months before a sporting event, the stencil is rolled out across the fairway, or the in goals / end zone / outfield and flower seeds and fertiliser is scattered onto the stencil.
By the time your event rolls around, the sponsors' logos are a blaze of natural colour.
Smaller scale domestic version also available with messages such as "Please pick up after your Pooch"-- ConsulFlaminicus, Nov 02 2005 peta pixel http://www.petapixe...ing-photosynthesis/ [pashute, Oct 21 2012] Mind the gap-- skinflaps, Nov 02 2005 You could do this with fertilizer too.-- bungston, Nov 03 2005 Why not make a rather heavy mat, place it down on your lawn and cut the grass that's still sticking up. Give it a day, the other grass will rise back up, and half the grass is 3 inches lower no questions asked.-- iamnafets, Nov 03 2005 I had that same halfbaked idea a while back, [iamnafets], but discovered it was baked.-- Shz, Nov 03 2005 Why was this idea not brought to my attention sooner?
In fact, just leaving the stencil in place for a few days would etiolate the covered grass, leaving the sponsor's message standing out in a deeper green.-- MaxwellBuchanan, Oct 21 2012 Works well until that awkward moment when the sponsor mergers or goes bankrupt. Eek, like trying to overdraw an old tattoo.-- Phrontistery, Oct 22 2012 This would be very good for making crop circles.-- Jscotty, Oct 24 2012 You could do color logos by using dandelion seeds, clover seeds, etc. in the stencil holes.-- phundug, Oct 24 2012 random, halfbakery