The Way Wood Works: Birch

Yellow birch rules

Although the birch family Betulaceae contains over a dozen domestic species,
between 80 and 90 percent of the lumber you’ll find at the lumberyard is yellow
birch (Betula alleghaniensis). Three other species are also commercially harvested
and may occasionally be mixed in with yellow birch. Paper birch (B.
papyrifera) is whiter,but softer.Sweet birch (B. lenta) is a bit harder and has a deeper
color.River birch (B. nigra) is more likely to contain knots.Birch boards average
about 6-in.wide, and are available in lengths up to 12 ft.Lumberyards usually stock
birch in 1- and 2-in. thicknesses.Home centers carry birch plywood,but may not
stock birch lumber.

Click any image to view a larger version.

Birch burl is prized by
turners.

Birch lumber is graded for color

Birch logs contain quite a bit of sapwood.
It ranges in color from
creamy-white to golden tan (with
occasional pink tones), and is
distinctly different than the reddish-
brown heartwood (photo, at
left). Commercial demand for
light-colored wood is so
strong that birch, like maple,
is often graded and sold
by its color. You’ll pay
about a 20-percent
premium for colorselected
birch.

At the lumberyard, birch boards
marketed as “sap” or “white” have
been color-selected. Sap birch refers
to boards containing at least 85 percent
light-colored sapwood.White
birch refers to paper birch. Some
lumberyards carry it separately
from yellow birch, specifically for its
white color. Paper birch boards are
usually narrow (about 4-in.wide),
short (6- to 8-ft. long) and thin
(1-in. thick). They’re best used to
make face-frames and moldings.

Most birch lumber is sold as natural
or unselected. There’s no difference
in the quality of the
wood—it just hasn’t been sorted
for color. Most natural boards contain
a combination of sapwood and
heartwood, but you’ll find lightand
dark-colored boards as part of
the mix.While light-colored birch
grabs all the attention, its deeper
toned heartwood (red birch) can
be just as attractive. Thick stock
(over 1 in.) is likely to contain
considerable heartwood. Lowergrade
No. 1 common birch lumber
contains more knots and other
natural defects.

Birch is famous for its light-colored
sapwood, but its deeper-toned
heartwood, which is known as red birch
in the lumber industry, can be even more
appealing.

Birch is a great impostor because its figure patterns closely resemble those in cherry, mahogany and walnut.
You can dress it up or down just by staining it different colors. Furniture manufacturers have used stained birch in
lieu of more expensive hardwoods for decades.

Birch plywood has many faces

Birch plywood is graded by its color, just like birch lumber.
The highest grade is white, followed by uniform
light and natural. Lower paint and shop grades cost
less.Hardwood lumberyards usually stock most grades.

The faces of white birch ply (here white refers to
color, rather than species) are made of top-grade (zero
defects), color-matched sapwood veneers. This architectural-
quality plywood has a handsome appearance,
but it’s expensive; around $75 per sheet.

Uniform light and natural birch ply have top-grade
veneer faces, in terms of natural defects, but they’re not
pristinely white in color. In the past, these grades were
distinctly different. Today, they’re virtually identical in
appearance (they’re both light colored) and in price;
about ten percent less than white ply. Paint and shop
grades of birch plywood are worth looking at if you
want to save money. They cost about $50 per sheet.
Paint-grade birch ply has face veneers that vary in color
and pattern match. Shop-grade sheets have some kind
of damage or manufacturing defect, but must be 85
percent usable.

It’s smart to shop for birch
plywood at a home center.They
typically stock a mid-level grade,
similar to the paint grade at the
hardwood lumberyard, but at
home center prices. This plywood
will vary widely in appearance
from sheet to sheet, and
will contain minor natural
defects, varying amounts of
heartwood and slightly less uniform
core material, but you’ll
save up to 50 percent, compared
to the top white grades at the
hardwood lumberyard. You’ll
also be able to look through the
stack for the best-looking sheets.
Take a friend along to help you
look, be careful, and leave the
stack neat for the next customer.

Top grades of birch
plywood are white and
uniform.They’re the
best choice if you want
a clean, pristine look.

Middle-grade birch plywood sold at home centers offers lots of creative possibilities.The
veneers may show attractive figure patterns, occasional spectacular curly figure, rich colors,
and any combination of sap- and heartwood, including all of one or the other. Staining will
minimize contrasting colors, but the only way to make these sheets white is to paint them!

Seal birch before you stain

Curly figure is common in birch and occasionally
it’s spectacular. Flame birch can
look as cool as tiger maple.Usually, though,
figure is a big nuisance because it’s randomly
located and hard to see. If you’re not
careful, a piece with hidden curly figure can
end up in the wrong place on your project.
One curly board in a tabletop will stick
out like a sore thumb, especially if you use
stain. It’s a good idea to check every board
for figure. Just wipe on some mineral spirits;
any figure will jump right out. If you’re
stuck with curly figure in the wrong place,
using wood conditioner before you stain
helps camouflage it.

Brush on water-based wood conditioner,
let it dry and sand lightly before you stain.This process
helps the wood absorb water-based stain evenly. Each
coat of stain adds a little more color.You can tweak the
color by using different colored stains, one over
another.Water-based stains dry fast, so you can put on
several coats in a day.

Stain makes
the curly figure
of birch look
blotchy.

Curly figure is subdued when you apply
water-based
wood
conditioner
before you stain.
In our
experience, two
coats of
conditioner may
be needed for
best appearance.

1. Keep it light. Waterborne
polyurethane adds no amber
color, so it keeps birch as light
as possible. Lacquer finishes are
also clear. Oil-based finishes add
an amber tone.

2. Imitate expensive hardwoods like mahogany,
walnut or cherry.To simulate the
open-pored appearance of
mahogany or walnut, use a single
coat of water-based conditioner
before staining.You’ll get an evenly
colored finish and some stain will
darken the pores, just like the real
McCoy.To imitate close-pored
woods like cherry, use two coats
of conditioner.When you stain,
the pores won’t show up at all.

3. Match old birch cabinets
or trim moldings that have aged
to a uniform honey color by
sealing new birch with two coats
of water-based conditioner, just
as if you were matching a closepored
wood.Then add color,
using a golden-oak colored
water-based stain.

4. Paint it. Because of its uniform
texture and tiny pores, birch
provides a smooth surface for
painting. It’s tougher than pine
or poplar, and unselected grades
cost about the same. For
cabinetry, even the ugliest birch
plywood will look great when
it’s painted.

Birch or hard maple?

Yellow birch and hard maple look so much alike
it’s often tough to tell them apart. Plainsawn
boards have similar figure patterns.They both
have pale sapwood and distinctly darker
heartwood. Manufacturers have used them
interchangeably for decades.

How do they compare?

– Hard-maple sapwood is whiter.

– Hard maple will make a better cutting block or
countertop, but yellow birch is tough enough
to stand up to normal dings and dents.

– Both show considerable seasonal movement.

– Both yellow with age.

– Birch machines better. Hard maple is
particularly prone to tear-out during edge
jointing, and burn marks from dull blades and
bits are tougher to remove.

– Birch accepts stain better, although both are
prone to blotching.

– Birch costs less. Although demand for lightcolored
wood continues to push up the price
of both species, birch is usually about
30-percent cheaper.

This story originally appeared in American Woodworker October 2001, issue #89.

October 2001, issue #89

Purchase this back issue.