The second species could be arrow bamboo, pseudosasa japonica, which is less vigorous but is still known to spread. As both plants are on boundaries and one has already started spreading ...

Bamboo is synonymous with China ... The network has conserved more than 23,000 species, accounting for about 60% of China’s native plants. More than 52 million tourists visit botanical gardens ...

The speed of bamboo growth puts other plants to shame. About 1,000 species of bamboo grow throughout the world. Actually a grass, the plant exists naturally on every continent except Antarctica.