What is the name of bamboo that slowly grows its roots and then is one of the fastest growing bamboos?

My Mum (trying to cheer me up) said I was like that bamboo.... slowly spreading my roots. Then one day.... I would rise very quickly.


Mum's gone now but I want to remember the name of bamboo.

What is the name of bamboo that slowly grows its roots and then is one of the fastest growing bamboos?
That describes most of them, particularly the winter hardy running varieties.





I have "nude bamboo" (phyllostachys nuda") and and it grows quite stongly in US zone 6.