Well, I have uploaded the foliage from Left4Dead 2. You can find the link here at my official Left4Dead 2 model pack thread: http://www.facepunch.com/showthread.php?t=847834
You can also download it here: http://www.filefront.com/15067809/L4D2-Foliage.zip/
I will post screen shots on both of these threads later.
By the way no, I am not uploading a map prop pack (maybe not) because over 50% of them are from Half-Life 2 or Counter-Strike: Source.