Do you know what sap wood means? and what is meant heart wood? and what is meant by the growth rings? These terms are very often heard when we talk about things related to wood, especially logs. But maybe for some people who are new to this field, do not know yet about the term of sapwood, heart wood and growth rings. For this reason, an explanation of those terms needs to understood. In brief, the understanding of wood circle is as follows:

Growth Rings
The formation of growth rings in a tree starts from the tree first grows until it is cut down. This growth rings formed once for each year and the number will continue to grow in the following years as long as the tree grows. The older of a tree age, then the more numbers of the growth rings, for example on a log, if the number of growth rings is 15, means the wood comes from a tree that has lived for 15 years. That is why the age of a tree can be known through the number of the growth rings in the body of the tree.

Then what about the shape of the growth rings? As the name implies, growth rings are in circle shape but that does not mean a perfect circle. Usually the shape of the circle follows the shape of the physical tree itself.

Sap Wood
What meant about sap wood is not a name for types of wood or tree species, but sap wood is the edge of a wood including all types of wood; teak, mahogany, rosewood, ebony, mindi, etc. Generally, sap wood comes in light or white, lighter than heart wood.

Heart Wood
What meant about heart wood is the middle or core of a piece of wood. Generally this part is darker than sap wood. So on a wood, between sapwood and heart wood clearly visible – like – there is a boundary separate them. But there are certain types of wood, such as sengon wood, which has similar color between the heart wood and the sap wood, so the boundary between the two is vague.

–sh