Round wood breaking with the thumbs

Breaking thin wooden sticks with the thumb, while holding it with the other 4 fingers.
-Warning: Should cause no damage to the pointing finger joint(s)

Interesting:
1 Going to thicker wooden sticks
2 Breaking a certain size and thickness into as many pieces as possible

Self making:
Round wood, not that thick, quit thin and sawing it into the right pieces of for example 15 cm long.