The Colours of Douglas Fir
The wood of Douglas fir is fascinating as it changes colour as the tree grows.
The outer layer is the sapwood – cells that are alive and have the task of carrying nutrients up to the leaves and sugars down to be stored, This sapwood is white.
As the tree grows, the inner layer of the sapwood dies and turns into heartwood which is pink in colour. As the heartwood is laid down, the tree produces chemicals which act as a preservative and prevents the wood from being attacked by fungal and insect infection. The heartwood makes timber that is very durable.
So, when we come to mill the round log into rectangular section boards, we end up with planks that have three patterns: those that come entirely from the heartwood and are pink throughout, those that come entirely from the sap and are white, and those that include some sapwood and some heartwood which are striped pink and white.
As we are milling our own timber, we can choose to use these different colour patterns and characteristics to best effect in making our log stores and bin stores:
- The base, on which the whole structure sits, is always made of pure heartwood – making use of its strength and durability.
- The sides are made of the mixed colour boards using the colour pattern to best effect.
- The white wood from the sapwood region is used to make the backs as these are the least visible parts of the structure.
The roofing is make of a a different species of tree – Norway spruce – which is white throughout and which gives us wide boards which are ideal for the tiling.
All timber that is exposed to sunlight changes colour over time from its natural colour to grey. The side that is more exposed to sunlight will turn grey more quickly that a side in shadow. The whole process can take several years and is completely natural and does not affect the strength characteristics of the timber.
We fell big Douglas fir trees to make our log and bin stores. The first picture shows a tree on its way down. When they are down, you can see that the log is a fascinating mix of white and pink wood.
See how we use these characteristics make a strong and attractive store