This is a little trick I found out while levelling my herbalism in Borean Tundra. This will help you skill herbalism in the early levels and is the best spot (in borean tundra) to do so since herbs in other places of the zone are quite rare.
This spot is located in "The Geyser Fields" just west of Taunka'le Village (Maps - World of Warcraft - the spots marked only circles the area, not any specific herb spots).
Now to the trick: You are going to herb Firethorn. It's a herb which drops either Fire Leaf (Fire Leaf - Item - World of Warcraft) or Fire Seed (Fire Seed - Item - World of Warcraft). They are not used by alchemy but are consumables only usable by herbalists.
The thing with Firethorn is that they, in addition to the herb, also burns with the new fire graphic introduced in WotLK. The good thing is that this fire is visible from a very far distance, long before you can even spot the herb itself. That way you can easily spot the herb from faar away. They grow on the high ground of the areas so a quick glance to a side can give you the answer if there's any herbs there without even having to get close enough to track! I found this very helpful while getting my herbalism up to 410+ (they were still yellow when I left for dragonblight).
Here are some pics for show:
Just a small tip for all you new herbalists in WotLK who are having a hard time skilling in BT. Enjoy!