I would never judge by the hair color. Why? My understanding is in each strain, the hair color is slightly different at it's proper harvest time. The recommended way to judge precise harvest time for cannabis is to read the trichome color. I learned that from some of the many experts that post here. What ya need to buy is a small hand held "microscope" at radio shack. It only costs around thirteen dollars or so. Don't try to harvest without it. Proper harvest time means alot.

Further, if ya want to really impress your self, you can actually control the type of high that your weed gives you, by how you time your harvest. If you harvest when there are only a few trichomes that are clear, you end up with a high that stays mainly in your head--cerebral. If you wait till most are cloudy, you get a good mix of body and head high. Since your dealing with a strongly sativa plant, you may not achieve a mostly body buzz, just by the nature of sativas. But if you had more indica influence in that strain, you could wait until almost all the trichomes were amber in color, and you'd have a couch-lock type high.---------Read up on it my friend. Tons of info here on all aspects of cannabis. Good Luck!