The stem in question is the one next to the green stake with the pointed tip. I live in Houston, Texas so climate it sub-tropical. This thing looks like bamboo but am pretty sure it is not. Its stem is thicker than the giant timber bamboo you can see in the photos next to it, yet more fragile. It grows faster than the bamboo (over 1" a day!) and doesn't appear to have any leaves or shoots from the stem. Is this a weed? If so, how to I kill it as the root goes deeper than I can dig and I am scared to killing my bamboo as its roots seem to run underneath my bamboo roots. Can anyone help?
It is bamboo. The same as the other. The roots are probably connected. It looks like a running bamboo, which is difficult to get rid of. It grows under the ground for awhile, then those shoots start popping up. The roots can grow several feet down. See the illustration of running bamboo here.
Thanks. Any recommendations on how I kill that bambook but not harm my giant timber bamboo? Any chance it can be Arundo Donax (Giant Reed)? http://calphotos.berkeley.edu/cgi/img_query?query_src=photos_index&where-taxon=Arundo+donax
I believe it is the same plant which you are calling giant timber bamboo. It is just putting out shoots.
It's definitely not giant timber. I have had this one come up before somewhere else where I didn't have any giant timber planted, and it grew straight up, no leaves, so nothing like new giant bamboo culms.
What you have must be Bambusa oldhamii, which is clumping and not running. See these photos of the new culms.