Usually leads to not so good things. Black sooty mold. Aphids. Ugly internodes (where the black sooty mold sticks to).

I've got about 20 species or so in pots. The don't seem to like my runners, but have an affinity for bambusa species (espically multiplex, like webgator said). Also seem to like Otatea species as well.

So what do you do to get rid of them? The same as Webgator suggests to do? Can a potted bamboo withstand a high prssure water jet blast? They are about 5ft tall right now so I don't know 1)if they'd handle it and 2) how high pressure a jet I should use?

Also, SoCalboo...Where do you get your plants from? I'm in Socal too and am just wondering where the best places are...

robanalog-
As long as you use a garden hose and not a pressure washer, and you stand back a few feet, they'll be fine. Think about how small the bug is and how big the stream of water is in comparison, and you'll see that it doesn't have to approach the speed of sound. Small bamboo will whip around, but, as long as you're not tearing foliage off, it'll be ok.
Also, if you have or can get some ladybugs, they love to munch through aphids.

Robanalog,

The aphids can be sprayed off, but the ants sometimes come back without the aphids, and they do so quickly. I have used ant bait traps with good effect, but don't like to use them around plants that come into contact with kids/dogs. The best method has been insecticides, but hate to use them.

As for places to buy, I bought alot from Pura Vida Tropicals, Bob Dimattia (Vista, CA). Awesome place to visit - huge specimens, plenty of stock and reasonable prices.

Bought a fair amount through mail order as well, Tropical Bamboo out of Florida (Ralph Saporito, i believe) and Bamboo Plantation (Jim Bonner). Both are very responsive, have good, healthy plants, and genuinely care that you get a good specimen.

Sometimes, it is not a good sign:
I found that ants "grow" mites which supply them
food from their "output" on my vivax leaves...
Here is the relation amount them

ants ----- eat material output from mites -------->
mites ---------- eat bamboo leaves -------------->
bamboo ---------> dying killing me :)

Ant baits containing sugar and boric acid are very effective in controlling this type of ant.
Tat and Terro are common brand names in US supermarkets,
They look like little shoe polish tins.

Ant's however are a SYMPTOM of another problem, scale, aphids, etc.

BTW, my Karr culms died after ants stay there for a while
- I don't know what they were interested in and what they
did there...Somehow Karr always attract ants but you should
check to see why if other species has ant on it - not a
good sign.

It's actually only in my Karrs. When I water in the pot they all come out of the bottom. I thought they just wanted moisture but I never observed that it was only in the pot with the Karrs. So how did you take care of the prob? The soap & water thing? I'm not using bait because I have 3 dogs and don't want them getting harmed. I should probably get them in the ground soon...

You don't really need high pressure water to apply soap--the soap kills the scales/mites/aphids by contact by dissolving their wax coat so they dessicate fast. If it's a small enough plant you can do it with a squirt bottle of soapy water.

Of course, the ants might bring in more aphids, but not every species of an imports its own aphids. Depends on what you have. You can keep many ants out of your pots with talcum powder (like baby powder, but not the corn starch type) floofed onto the sides of the pot, or some other physical barrier. That isn't too practical outdoors of course...I can't imagine the stuff sticking around too long where there's weather.

i noticed ants going in my karr pot as well as another green bamboo species (dont know the name)..ive temporarily sprayed insect spray from where they were coming from to kill their entire chain..however im afraid theyll be back..i do notice something dirty looking on the leaves but it gets easily cleaned when i spray water on it..i think its just dirt

the ants are going up the stalk probably on the leaves..but i never noticed any aphids on my bamboo leaves..are they visible??