Why Is Heartwood Darker Than Sapwood?

To get the job done right you need to have the right tools. But it’s equally – if not more – important to make sure you are using the correct material for your project as well. When it comes to woodworking, not understanding the varieties and uses of different wood types can lead to sub-par quality work or even a totally failed project.

And two of the most common questions that I hear people ask are “why is heartwood darker than sapwood?” and “what are the different uses of heartwood and sapwood?”

So that’s what we are going to cover in this article. Basically, what is the difference between these two wood types – heartwood and sapwood.

You might be surprised to find that both of these wood types come from the same tree. In fact, many people believe that one species of tree provides heartwood and another sole species gives us our sapwood. In reality, all trees are made of both sapwood and heartwood.

Heartwood is the dead, inner wood of a tree which will make up the majority of a trunk (stem) or branch’s girth. Sapwood is the outermost, living part of a trunk or branch.

All trees begin life as sapwood but as they grow, the sapwood (xylem) cells die and become the non-living heartwood that makes up the bulk of the trees cross-sectional area. The sapwood can be viewed as a kind of living skin around the tree but instead of shedding this skin, a new layer is grown over the old.

Why Is Heartwood A Lighter Color Than Sapwood?

As living matter, sapwood’s role in the function of a tree is to bring water and nutrients gathered by the roots and distribute them to the rest of the tree. It does this through a network of thick-walled cells.

As time passes and the tree grows and expands in girth, the cells at the center of the tree die and harden, trapping and storing sugars, oils, and dyes in this dead wood that we refer to as heartwood. This part of the tree is also known as the duramen.

It’s this process that gives trees the rings that you see on the cross-sectional area of a fallen tree.

And it’s this process that gives the heartwood its darker color. As the sugars, oils, and dyes dry up inside the dead wood, they turn the wood a darker color than the living and hydrated sapwood.

Is Heartwood Better To Work With Than Sapwood?

Short answer – yes.

While a healthy tree needs essential water and nutrients to live and grow, moist wood does not suit most woodworking projects.

For woodworking, we want the hard, dead, dry heartwood found in the center of the trunk or branch, as it is a lot easier to work with and yields far better results.

The basic rule is – the lower the water content of the wood, the better it is to work with.

And even when working with heartwood, it’s possible to make the wood even stronger and more durable by putting the wood through a stabilization process. This may include processes such as impregnating the wood with resin or filling cracks with epoxy. This can be done with both heartwood and sapwood.

Is All Heartwood Darker Than Sapwood?

Don’t be fooled into thinking that just because a piece of wood is light-colored, it’s sapwood. Or if it is dark, it must be heartwood.

In an individual tree, we can always recognize sapwood as being lighter in color than heartwood but the thing to remember is all species and varieties of trees have different colored woods.

Basswood, Cottonwood and Fir trees all have light-colored heartwood at their core, as do most varieties of Spruce trees.

And some sapwood can turn dark in color if affected by illness or fungus.

How To Harvest Your Own Wood

One of the great pleasures of woodworking is when you are able to create a work from wood that you have gathered yourself. There is something very satisfying about taking something from nature and being involved in the entire creating process. So, as a bit of a footnote to this article, I’m going to add this section here about the tree feeling process.

First and obviously, you’ll need to have access to land where you can legally fell trees and have permission to do so.

Once you know which tree you want to fell, there are some safety precautions that need to be addressed.

Make sure you follow these safety precautions whether you are using a saw, chainsaw or an ax.

  • Remain focused at all times when handling sharp cutting tools
  • Use the correct tools and equipment
  • Wear adequate protective equipment such as goggles to keep debris out of your eyes
  • Wear protective gloves to help maintain a firm grip on your tools
  • Estimate the felling zone and make sure it is safe
  • Clear the cutting zone of trip hazards
  • Have at least two people felling the tree if possible
  • Make sure you are adequately trained and know how to handle your tools

I recommend watching the video below as a great guide on how to cut down a tree safely.


I hope that I have managed to clear up any queries you might have had about the differences between heartwood and sapwood.

The most important points to take away from this article are:

  • Heartwood is more desirable to work with than sapwood
  • Heartwood is the strong, supportive dead core of a tree
  • All trees contain both heartwood and sapwood
  • All trees start out as sapwood
  • Heartwood can be light or dark in color depending on the type of tree

Understanding this will help you make a more informed decision when deciding on the right type of wood for your project.

Thanks for reading and please feel free to drop us a comment about your experience working with sapwood and heartwood.


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