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For what I understand, For bubble hash we are targeting the Caps only. Frenchie methods like to collect all types of trichomes. This method only targets the caps which is holding the terps and thc.
If I remember right, I think their or 4 types of Trichs and not sure if the other 3 hold much thc, could hold other stuff. I really enjoy this way because its low cost, less work (using drill) and the rewards are delicious.
@VAkish True, It would be more effort for a similar outcome.