Hello,
When alpha to coverage with all trees + grass is enabled, blue lines appeared in pine trees as well as having a "pixeled/grid/dithering" affect if you look close enough.
http://i.imgur.com/LA9hVZo.png
I can confirm that when .60 was in experimental, the blue line bug appeared for Nvidia cards, but since then has been patched, but not for AMD/ATI cards.