What's the biggest, thickest timber type bamboo anyone has encountered in Florida?

I recently found a stand/grove of massive timber type bamboo with culms having a diameter of about 5-6 inches. It's rather curious in that its growing in the middle of a vacant lot, a lot that has been vacant for many years, so its getting no supplemental irrigation or fertilization and is in competition with many pines, palms and grasses growing wild all around it and among it.

Im gonna dig some up (clandestinely).

I know that some truly tropical areas have big boos, but whats the biggest boo youve encountered in Florida? (other than in a place like Fairchild, Selby or some other specialized plant zoo where a staff cultivates and encourages growth.)

Any tips on digging out this massive boo? I know the more root/rhizome the better, just wondering if anyone has any helpful hints.