Well recently, ive created some displacements for my map, and a shitload of 2d plants were coming up and floating about it and whatnot, it was horrible. And eventually began causing errors in my maps. I asked around to a few people and they had the same problem and it was very irritating. So i started doing some research.

If you want these plants gone all you have to do is go into details.vbsp which is located in steam\steamapps\common\left 4 dead\left4dead
You can manually adjust the amount of these sprites that show up by opening the file in notepad, and manually decreasing the amount that show up under the desired texture. If you want these plants gone all together just move details.vbsp into another folder, DO NOT delete it though, for you may want it for these plants later.

I know a lot of the people here don't map for source, but i posted this for the few people that do, and i prefer them gone all at once.

NOTE: these plant sprites that show up will show for almost every blend texture, excluding cliffs.