B. beecheyana is one you might want to try.

Other large clumpers are the Dendrocalamus', such as Brandisii, Gigantea, Asper, and Latiflorus. The Guaduas also get very large, but most have thorns. The Dendro's have the largest and tallest culms of any bamboo known, but they are NOT cold hardy. If the temps get below 30F, they start to lose leaves and even a frost will burn them.

My Dendrocalamus and Guaduas burn each year here in z8, and never grow to more than just bushes, but if you protect them and it doesn't get below 30F, I'd try them and see what happens.

On the other hand, there are many runners that are large and would probably do well in your area, such as P. vivax or maybe giant black.

Good Luck

Kt

The complete environmental picture determines what kinds will grow for you. That includes occasional severe cold snaps, how long normal cold persists (does the soil become chilled by weeks of cold every year?). Many plants that are touted as being hardy to a certain low temperature do not tolerate such cold for periods of weeks or months. A couple nights in the 20s followed promptly by a return to summerlike conditions is not that same as frost and snow for weeks (or months) every year.

B. tuldoides varieties, such as PUNTING POLE, 'Ventricosa' BUDDHA'S BELLY, 'Ventricosa Kimmei', or CloneX. I grow these here(except CloneX) and they do very well.

B. malingensis, B. pachinensis, B. pervariabilis 'Viridistriatus', B. eutuldoides 'Viridivittata', B. chungii, and
all of the textilis varieties do well here. The cold is their only enemy and it isn't that bad.

Temps into the mid 20's did little, if any, damage to them this year. Nighttime lows range from mid 30's to upper 40's. Daytime highs range from low 50's to the 70's.

A few years back, some were completely covered in ice for almost one full day, but the temps didn't drop below 28F, so they had little damage. Snow won't be a big problem as long as it doesn't get extremely cold and as long as it doesn't stay covered in snow for long periods of time.

If you have oldhamii, tuldoides, textilis, dolichomerithalla, and h. hookerianus teague blue, then these will do well also. Your high altitude may be more of a factor than the cold, although I can't say for sure since I'm in Texas. Your area is a whole 'nother country. The Bambusas do love heat and high humidity so they are suited to this Texas climate, yet it could be a bit warmer in the Winters.

Any of these are definitely worth trying but may need Winter protection in their first couple of Winters and keep them watered well during all Winters thereafter.

Good Luck

Kt

Here in TX, and I presume in CA, there is too wide a range to say what Bambusas grow well in Zone 8. It is the minimum temperatures that occur, usually in the very early morning hours that do the damage. Each individual plant can vary in hardiness and I think some adapt somewhat to the lower temperatures.

I am in USDA Zone 8b about 50 miles north of Kentuck. Our minimums sometimes get down around 18 F most years. B. Multiplex, textilis, tuldoides and ventricosa all do reasonably well here but another 80 miles north of here in Zone 8a B. ventricosa struggles and tuldoides also gets some more damage. Their areas even further north, still in Zone 8a, where even more damage occurs.

If you are not sure what your minimums are I would try B. textilis first and see how that does after a couple of years in the ground. If your minimum temperatures do only get down to the low twenties then, as Kentuck says, you have several choices.

Mike near Brenham TX