In a previous series on the topic of lumber color change, we took a fairly surface-level approach. This time, we’re going to delve a little more deeply into the many factors that contribute to differences in color. First on the list, grain probably influences color variation within a species more than any other factor.
Grain Caused by Density Variation
Even when milled from the same tree, the color of two boards can vary greatly based on the way they’ve been cut and the part of the tree from which they’ve been cut. What impacts the way grain influences color is often density — which, in turn, determines how a board reflects light, and how its color appears to our eyes. (For more about the science behind how light reflection translates into color, check out this website.)
If trees grew perfectly straight, causing wood fibers to be completely parallel to one another, the density throughout a tree would be uniform. However in reality, grain flows over and around knots and moves to stabilize the tree as it fights against wind or gravity, causing the density of a tree to vary.
Grain Caused by Seasonal Shifts
Growth periods also impact grain, with less dense wood formed during times when growth rings are spread further apart and denser wood when rings are grouped more closely; sometimes you will even find some of both within a single tree due to annual climate variation. Then add in figured, curvy grain and the potential for exposing end grain on the face of a board in order to display intricate quilted and curly effects. In such situations, the color can vary drastically even within a single board.
Grain Caused by Sawing Techniques
Not only does the grain that naturally occurs contribute to the color of a board, but the technique used to saw it from the log also makes a difference. Essentially, by using a particular sawing method, we’re choosing which type of grain to impose upon a log. If the board is cut from the periphery or the center of the tree, the board’s appearance will be affected, as it also will whether Rift or Quarter sawn boards are cut from the log.
Even with those premium cutting techniques that tend toward showcasing parallel grain, flecks referred to as Medullary Rays can show up on the face, presenting the board as being uniformly darker than others cut from the same log. Sometimes these boards display a striped pattern, instead. As you might imagine, end grain is always darker than face grain, as well.
Of course, grain isn’t the only factor that impacts wood color. In Part 2, we’ll look at the following additional contributing factors:
• Harsh Environmental elements
• Regional Climate Distinctions
• Difficult Traveling Conditions
J. Gibson McIlvain Company
Since 1798, when Hugh McIlvain established a lumber business near Philadelphia, the McIlvain family has been immersed in the premium import and domestic lumber industry. With its headquarters located just outside of Baltimore, the J. Gibson McIlvain Company (www.mcilvain.com) is one of the largest U.S. importers of exotic woods.
As an active supporter of sustainable lumber practices, the J. Gibson McIlvain Company has provided fine lumber for notable projects throughout the world, including the White House, Capitol building, Supreme Court, and the Smithsonian museums.
Contact a representative at J. Gibson McIlvain today by calling (800) 638-9100.