LG,
Which map is your problem occurring on? I'd like to look it over, if I have it in my BAT 4.0 game.
The only such grass clump objects I've found so far are tied explicitly to the Runway object of type "ground", meaning the common grass covered strips. There are 1490 polygons comprising these individual clumps, and are present only for the first LOD (which is why they are visible only over a rather short distance.) I've looked at them at night, with light sources nearby, and they appear normal.
The grouping of the objects in your video suggest something different, although it being so dark I couldn't discern clearly how the airfield was built up.
If your problem objects are indeed these very same things tied to the grass runways, then I suspect the shininess in the dark might arise from some light source in the vicinity which has a an emit value larger than 1.0. This is suggested by the brightly lit cloud over a flare or some such object.
Can you verify if the brightly glowing aspect is in effect when all is dark, with no light sources anywhere nearby?
Glenn