That is most likely spider mites. It all starts off as the plant not growing as quick as it should, then you notice light bleaching effects on the tops of the plants,then you see small bites, next thing you know you see webs! Dont feel bad, you cant really see a mite infestation starting out unless you check with a loupe every day. If you have webs from one cola to the other, then thats a big spider. Webbing from the top to half an inch to an inch down could very well be spider mites. Regardless of the situation, even though i dont have them, and a friend says something about mites, then i will be scoping my plants for the next 40 hours just because i cant get it out of my head. Yes, thats how bad those little shits are. Any small white/gray dots could be mite waste or nymps (baby mites) they can be found anywhere even buds and if they are feeding in the flowers itself, they will get stuck between trichomes when they mature into adults!. The black dots will be adult mites, often above and below fan leafs only. Also, its that time of the year for mites anyway! Gonna go home and do a checkup thanks to this thread.