Growth and shaping of bamboo poles
An earlier blog explained the difference in colors and hardness of different types of bamboo, but what determines the thickness within a species? There’s Guadua poles of ø 5-7, but also Guadua poles of ø 13-15 cm and sometimes even bigger! You can also experience a difference when, for example, you order 3 poles of ø 9-11 x 300 cm. In this blog we explain how that works.
Bamboo grows at lightning speed. In that rapid growth, it removes a lot of CO2 from the air. This stores the bamboo underground. Bamboo does not only grow in height, but also in width under the ground.
In that respect, bamboo comes in two types: clumping and running bamboos. Thanks to running bamboo sometimes half of the forest is growing from one rhizome. In nature, this is good for beautiful forests. This first plant still must fight hard for its place in the ground. The bamboo that emerges from these underground roots, on the other hand, already has a nice network to meet the needs for successful growth. So, you can plant a small bamboo plant that will produce huge new plants in the years to come. These huge shoots emerge from the ground and this gives more and more super strong bamboo to harvest. With clumping bamboo it is actually that 1 bamboo is the mother. Other plants grow from the underground clump of that one bamboo. You can recognize these in the wild, for example, as a cluster of bamboo together.
The way of growing determines to a large extent how thick the bamboo is. Unlike a tree, bamboo above ground does not grow wider the older it gets. But the bamboo does not emerge from the ground as a mature tree. As you can see in the photo, despite the size, they are real shoots. Eventually, these grow up to 30 meters high. As a result, bamboo is always a bit tapered. This means that there is a margin difference in the ø (diameter). This means that it matters which side you measure the pole from. You hardly notice the difference with posts up to 2 meters long. With posts from 3 meters and up you can give an approximate percentage to it. Guadua, for example, is a lot firmer in diameter and tapers on average about 10%. With Moso bamboo this can be about 20-30%. But that does not mean that there is a difference in diameter in your pole. It is not always the case that there is so much turnover. This has to do with the position of the stick within the entire bamboo.
For example, a Moso bamboo can grow up to 28 meters high. If you take out 3-meter poles, some will be more at the top and others at the base of the bamboo. The degree of tapering is determined by which part of the plant the pole comes from. Of course, we always keep in mind that those margins are as small as possible.
In addition to the degree of taper, the distance between the nodes (or internodes) also says something about which part the pole comes from. At the bottom of the bamboo, for example, many nodes are relatively close together. As it grows, the space between the nodes will also grow. At the top there is less and less space between the nodes. The nodes provide the bamboo with strength. It is therefore efficient for the bamboo to have less space at the bottom between the nodes. This ensures a strong base. The space between the nodes is partly determined by species. Some species have longer internodes than others. Circumstances also play an important role here. More water means larger internodes.
So based on what your bamboo pole looks like, you can estimate where it comes from the entire pole. For example, more space between the nodes and less tapering comes from a lower part of the bamboo.