To add to the comments already posted; Some countries also have programs that combat invasive plant species. I once worked in such a program which removed invasive American trees in Europe.

probably because it needs to be artificially moved elsewhere, and unless it moves in large enough quantities it’s outcompeted

Himalayas and Siberia stops natural expansion, farmland essentially corner it, everywhere else it could grow is also already occupied

There is definitely some invasive bamboo in the forests near me that’s spreading and taking over the native habitat

I have bamboo on the back corner of my property (two different types) and let me tell you that it is a never-ending war to keep it as a fairly thin line (it’s basically my privacy fence). On the plus side, it’s really good at holding the ground together, supposedly, which helps living in earthquakeland.

Same question for morning glory, blackberries, and every other kind of wildly spreading thing.

Well it doesn’t take over my yard because I got it all removed by a guy with a backhoe because it scared me. I like the way it looks but want some clumping bamboo not running bamboo, which had taken over the yard here when we bought our house. There’s still a little in one corner I just aggressively manage it. Comes over from the neighbors so it’s unavoidable.

There are bamboo forests, aren’t there? I’m sure that in its natural habitat it does have competition. Like kudzu. It’s just invasive here.

Bamboo is kind of a tree in this case which is an area I know more about and I think many of these factors would apply to bamboo as well. First forests used to actually be more rare than today before humans came along. Europe and North America was covered by endless plains which were grazed by huge numbers of ruminant animals. Any tree that would try to grow would get grazed before it could grow so tall that the animals couldn’t eat it anymore. That’s why grass thrives in such an environment, it’s practically made to get grazed. Once cut it quickly grows back again. Once ancient humans came along and hunted most of the grazing animals extinct forest suddenly started spreading like crazy until almost the entirety of Europe was forested (which was then to a large extent deforested again after agriculture was invented). Grass simply can’t compete against trees for sunlight. Therefore I would expect less or none bamboo in areas with a huge grazing wild life populations. And I don’t mean animals that would eat the leaves, but the ones that would eat the new seedling.

Another thing that limits trees is moisture. In general the drier the climate the less beneficial it is to be a tree. That’s because deep roots are of no benefit in dry climates (but they are of huge benefit in humid climates during drought). Grass which generally have very shallow roots suck up all the rain before it can penetrate deep into the soil while deep tree roots never get any significant amount of water. Trees handle drought well but constant dryness is very detrimental for them. Dry areas also tend to have wild fires which also hamper trees. It’s simply better to be a grass (if moderately dry) or a cactus like plant if it’s extremely dry.

Another factor is soil conditions. Now I don’t know what soil bamboo prefers but I doubt it’s all soil. Soil can have huge impacts on things like pH and water availability. For example in far Northern Europe where I live you can tell that you are standing on sandy soil if all around you are spruces and pines. If you however see lots of leaf trees you are probably on a silt and clay soil. This is because conifers handle both dry and sour soil better than the local leaf trees which leads to more conifers on sand. Bamboo is probably also limited to a certain soil condition.

I hope that can at least help you develop more theories on why bamboo is not everywhere. Something important to remember is that just because a plant can grow well in a certain location doesn’t mean it will be found there. That’s because plants are always in fierce competition. I bet bamboo if intentionally planted and cared for could thrive in lots more places than its found naturally, but it just happens to not be the best plant in that location, meaning it’s outcompeted over long time scales.

Soil composition, access to water, temperature/seasons, mountains, salt water, etc.

It needs nutrients, water and heat, without access to that it just doesn’t grow or spread fast, or at all. So it can’t cross the deserts on its own. It can’t grow above a certain sea level so it can’t cross the mountains(Pandas regularly have to climb down the mountains to get more access to bamboo)., it can’t use salt water, it can’t grow if it gets too cold for long periods of time and so on. It’s just fast growing in ideal enviroments.

The big horror stories in regards to gardning, isn’t that it throws seeds around and just grows everywhere. It’s that once one seed as taken root, it will start growing rhizomes. Which are similar to roots, except it’s a stem that grows horizontally underground. And famously bamboo stems will grow through most things very quickly. So if you don’t put up a proper root barrier, they will grow across the nearby lawns and start sprouting roots and and shoots. And from what I remember each shoot can grow more rhizomes, so you have to basically dig up the entire area or use strong plant killing agents and go without a plants in the area for a while.

Pandas, yo.

Climate for one. At least where I’m at its too cold for bamboo to grow. Even in peak summer it’ll try to spread but its only a matter of time till the frost destroy it.

Now kudzu on the other hand. That shit is fucking up everything.

Pandas

The tiki bar industry.

Bamboo rats feed on the underground roots of bamboo plants.
I’m not sure how much of an impact they make, but I can imagine they keep some of the growth in check.

If you broaden your question only slightly from bamboo to bamboo and its close relatives, then it has taken over the world. It’s in the grass family, and in no small part thanks to humans, it’s literally everywhere.

You should read Semiosis, a sci-fi book about a planet with a lot of bamboo.