How to Tell Maple Plywood from Birch

Made into plywood, the two species look similar. Here are tips on telling them apart. January 11, 2007

Question
I'm having trouble distinguishing clear coated birch ply from clear coated maple ply. Let's say the coating is polyurethane. Are there some key differences I can look at?

Forum Responses
(WOODnetWORK Forum)
From contributor W:
The first essential resource is Bruce Hoadley's book entitled Wood Identification. A fast Google search (wood species photos) will turn up a number of links that will include photos. However, since color reproduction on computer monitors is notoriously inaccurate, I'd suggest that those will be useful only to look at typical grain patterns. Bottom line: Get a copy of Hoadley's book, because it will not only aid in identification, but give you a good description of the characteristics of each species.



From contributor L:
Birch will have more of an amber cast to it than maple, which will usually look much whiter. When you buy it, you will see the difference - $$$.


From contributor J:
My grandfather taught me to look at the peaks of the grain cathedrals. Maple peaks are generally more rounded and birch peaks are sharper and more jagged. Of course, there is always the exception.


From contributor E:
There is also usually a stamp on the edge of the sheet which tells you what it is. And sometimes it doesn't matter which wood it is. For example, I use pre-finished maple ply for all my cabinet interiors. If I substituted a piece of white birch, who would know? I do think that the grain in birch is a little darker than maple, although that's just from my experience with it. Others may certainly correct me if I'm wrong.


From Professor Gene Wengert, forum technical advisor:
Telling the difference without magnification is very difficult. But the properties are certainly different. Considering hardness, hard maple is 1450 pounds, soft maple is 700, yellow birch is 1260, and white birch is 910. If hard maple is dried at too high of a temperature, it will redden a bit.


From contributor M:
Under a clear coat, as stated, there's a bit more of an amber hue to the white birch than the maple. And there will generally be a bit sharper delineation in maple between early and late wood when you look at the board. Often it looks like a fine, dark pencil line. Conversely, white birch's terminator lines between early and late wood are much more subtle, often showing themselves as a change in light reflectivity more than anything. The working properties are a bit different, also. Maple's sugar content is dramatically higher than birch's, and as such it will be more prone to burn marks when routing or cutting than birch.

Under stain, however, the differences are much more pronounced. Birch, being a diffuse porous wood, blotches badly under stain - much more than either hard or soft maple. So the finishing schedule needs to account for this tendency much more than if you're working in the maple family. Ultimately with white birch, it pays to think dye instead of stain.



From Professor Gene Wengert, forum technical advisor:
Hard maple can indeed be whiter, but not all hard or soft maple is whiter than birch. The lines that contributor M mentions are actually the annual growth ring lines and are between the latewood of one growth ring and the early wood of the next year's growth. They result because of special wood cells called terminal parenchyma.

Hard maple does indeed burnish or burn under a knife when the wood does not move fast enough. The burning is due to the density difference and not the sugar content. Finishing varies among the species mentioned. All the woods mentioned are diffuse porous. Finishing differences are due to density differences.

Note that the various birches cannot be separated from each other, even under magnification. Hard and soft maple can be separated easily using 10x magnification by observing the ray width. Birches can be separated from maple with 10x magnification as the pores in the birches are much larger in diameter than the width of the rays, while in maple they are approximately equal to the width of the rays. One other difference between maple and birch is that the maples tend to have a conspicuous ray fleck on radial surfaces.