It's a Phyllostachys, and I think I know which one, but I'll go through my reasoning first. If it took sub zero temps that rules out some species like P. aurea and its varieties, as well as the bigger timber bamboo that also have yellow culms.
The spp. that can handle sub zero cold are almost exclusively green culmed (P. nuda, atrovaginata, angusta, bissettii, aureosulcata, stimulosa), however, P. aureosulcata has 2 varieties (+ 2 others that are 'mixed' in colour) that have mostly yellow culms. One is P. aureosulcata 'spectibilis' which is often regarded as one of the most attractive bamboos in cultivation, and has the benefit of holding some green into sub zero temperatures.
The other aureosulcata that has yellow culms is P. aureosulcata 'aureocaulis' a very hardy and exceptionally beautiful bamboo. I know of people in Quebec Canada growing this bamboo is zone 3/4 (by bending it over in the winter), so it is very tough! Great find, it'sone of my favorite bamboos, but if you want to try it be sure to give it room because n a very short time it will invade a large area!
Here is a website about it:
http://www.bamboogarden.com/Phyllostach ... aulis'.htm
And here is the plain green form in my zone 4/5 garden after a winter down to -20f:
<img src="
http://inlinethumb30.webshots.com/32797 ... 600Q85.jpg" alt="002">