What you're observing is very common with many species of running bamboo.

It is my understand that rhizomes are put out by clumpers also so I have a follow-up question.

Being eager to see more clums soaring into the sky, how soon should rhizomes be separated from their parents?

Is rhizome separation an acceptable way to accelerate expansion of the clumps?

Clumpers do not put out rhizomes like runners; they have a root mass that expands slowly in all directions. In order to propagate from a clumper, you need to extract out a decent size chunk of root mass with one or more mature culms (not "clums") attached, and plant in another location. This is a rather challenging task if you are unexperienced with dividing clumpers. The root mass is dense and woody. You can't just try to dig up a part of it: you need to use tools like a sledge and a steel shovel that you can pound through the root ball. Then, if you have not taken a big enough piece or have mangled it badly, the division may simply die. I'm not trying to discourage you...just injecting some reality based on my own experiences over a number of years.

I BOUGHT 5 GIANT TIMBER BAMBOO RHISOMES AND PLANTED THEM A MONTH AGO. QUESTION IS.... HOW LONG ON AVERAGE UNTIL SHOOTS START COMING UP?????? SPECIFICALLY FROM RHISOME NOT SEED!

Just rhizomes, no topgrowth?

If you haven't seen anything in a month, then they're probably dead.

If you got rhizomes with some shoots or other topgrowth with them, then it may be a year or so before you see shoots, and even then, they will be small.

Kt

rik-
Let me guess...you bought them on eBay? There are many people selling rhizomes on the Internet, but this is not a good way to try to grow bamboo. It can be done, but, even if you are experienced and have very fresh rhizomes, the success rate can be very low. As kentuck points out, you really need some healthy top growth (with an intact rootball) in order to improve your chances of success. Those of us who are into collecting bamboo typically only get/trade complete plants because we don't want to wait for years to get a decent size specimen.