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urban &
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    kinds of plywood
Like all wood, plywood falls into 2 major categories: softwood & hardwood. Softwoods, conifers such as pine & fir, tend to grow faster than most hardwoods, and make less expensive panels that dominate applications for the construction industry such as roof decking, subflooring and wall sheathing. Hardwood panels from broad-leaved trees such as oak & cherry, find their way into furniture, cabinetry, and high-end paneling. Tropical hardwood plywood is an exception, since its low price has allowed it to be used extensively in construction, such as concrete forms for the Japanese building trades.

Plywood is also graded for appearance & number of flaws (see below), with a 2 letter code indicating how good its front & back are. AC plywood, then, has one 'A' face and one 'C' face. If the grading stamp incl a pair of numbers separated by a slash, such as '32/16,' that means rafters should be no further than 32" apart if the sheet is used for roof decking, and joists no more than 16" apart if it's nailed down as a subfloor.

plywood veneer grades
A = Smooth, paintable. Not more than 18 neatly made repairs, boat, sled, or router type, and parallel to grain permitted. Wood or synthetic repairs permitted. May be used for natural finish in less demanding applications.

B = Solid surface. Shims, sled or router repairs, and tight knots to 1" across grain permitted. Wood or synthetic repairs permitted. Some minor splits permitted.

C plugged = Improved C veneer with splits limited to 1/8" width and knotholes or other open defects limited to 1/4" x 1/2". Wood or synthetic repairs permitted. Admits some broken grain.

C = Tight knots to 1.5" Knotholes to 1" across grain and some to 1.5" if total width of knots & knotholes is within specified limits. Synthetic or wood repairs. Discoloration & sanding defects that do not impair strength permitted. Limited splits allowed. Stitching permitted.

D = Knots & knotholes to 2.5" width across grain and 1/2" larger within specified limit. Limited splits are permitted. Stitching permitted. Limited to Exposure 1 or interior walls.

Anyone who used disposable chopsticks understands the problem that plywood is designed to address: when you pull the 2 sticks apart, the isthmus joining them breaks with a satisfying snap. In general, all wood is like that, much stronger across its grain than parallel to it. Thin pieces are flexible & light, but they can scarcely hold any weight. The ancients knew this, too, and developed a crude form of what we know as plywood. Their solution dating back to the tombs of second millenium B.C. Egyptian pharaohs was to glue thin slabs of wood together with their grain running perpendicular to each other. The strength of one ply compensated for the weakness in the next. Similar ventures are known from ancient Rome, China and 17th century France.

It wasn't until the Industrial Revolution met the great forests of the Pacific Northwest, however, that plywood made its mass-market debut. The prototype panels were trotted out for the 1905 World's Fair in Portland, produced one at a time, clamped with house jacks and held together with animal glue which stank so bad that the workers had to leave the mill frequently in search of fresh air. Since then, plywood has become so widely used that in 1995 enough was produced worldwide to cover a football field to a depth of eight miles. About two-thirds of that is used in just 3 countries: U.S., China and Japan.

how plywood is made
The process of making plywood has become ever more sophisticated. To start with, logs are cut to lengths of 8.5 ft, stripped of their bark and steamed for softening. They are then mounted on a lathe and spun at a few hundred revolutions per minute. A sharp knife peels the log into a single running strip of veneer between a tenth and a quarter of an inch thick, depending on the kind of plywood being made. The process is so quick that a medium- sized log, 2 ft dia., can be reduced to about 400 ft of tenth-inch veneer in a matter of 10 or 15 seconds.

Because the log is sliced with a knife, none of it is lost to sawdust, although some is wasted in the process of reducing an irregularly shaped log to a true cylinder. Over time, systems have improved to discard less & less of the center core at the end of the process. It used to be that veneer lathes would stop peeling when the remaining core was just large enough to make a pair of two-by-fours or a fence post. New technologies allow veneer-makers to peel logs down to a core barely thicker than a broomstick.

Once veneers are made & trimmed to standard lengths, they must be handled carefully so they don't tear. The sheets are dried in a kiln, and some are then patched. Higher grades of plywood must have all their knots cut out & plugged with any of the standard sized wood patches, such as the familiar football or eye shaped repair.
The sheets of veneer are then laid up in stacks & glued, with the better-looking veneers on the face & back, and the unappealing, irregular or knottiest sheets in the center. The glued sheets, almost all made in the familiar 4x8 ft size, are then sandwiched for about 5 minutes in a hot press. Some final repairs are made with resin, the panel is sanded, and it's ready for use.

industry adjusts to the scarcity of big trees
The last 20 years have seen significant changes in the raw materials used to manufacture softwood plywood. At the outset, the western plywood industry relied heavily on large, flawless old-growth Douglas-fir logs. These trees yielded lots of near-perfect veneer, providing panels unmarred by knots or patches. But as top-notch trees have become scarcer, they are in greater demand for solid lumber that is clear of knots, or as standing forests to provide habitat for the spotted owl, marbled murrelet and coho salmon. The industry adjusted by retooling for smaller logs, and customers adapted by reconciling themselves to knot repairs in their plywood. Where softwood plywood was once made from 6 ft dia. logs, now it comes primarily from logs that are at most 2 ft across.
At the same time, much of U.S. softwood plywood industry has shifted from the Pacific Northwest to the South & Southeast, where pine plantations abound on private lands These small pines produce a lower quality panel than older trees, says forestry consultant Dobbin McNatt, who recently retired from a 33-year career at the U.S. Forest Service Forest Products Laboratory in Madison, WI. These southern pines are typically cut by the time they hit 30 years old, and are made up in large part of "juvenile wood," he explains, which is more prone to warping than older fibers. "I've seen it put down as underlayment for a floor in real dry conditions in the winter and then turn wavy in the summer," he says.

the hamburger of panels: oriented strand board
The wood products industry responded in still another way to the declining supply of large logs. In the process, they also dealt with the labor-intensiveness of conventional plywood making. They developed a panel called "oriented strand board" (OSB), made up of layers of wood chips about 3" or 4" long by 1" or 2" wide. Successive layers are arranged with the grain running perpendicular, just like plywood veneers. Machines deposit these very uniform chips on a form, add glue, and press a fluffy stack that might start out 6" or 8" tall to a thickness of less than half an inch. OSB does for structural panels what press logs do for firewood: provides a way to manufacture an absolutely uniform product with lots of machinery & little hands-on labor. Where a plywood mill might employ a couple of hundred people, there might be just three or four on an OSB plant's shop floor. It also allows the industry to make structural panels out of hitherto less-exploited species such as aspen. These differences are reflected in the price, too: about half the cost of comparable plywood products. As a result, OSB has grown from a relatively small business in the early '80s to nearly two-thirds the volume of the plywood industry in 1996.

But OSB can't take the place of plywood in all situations. Apart from aesthetic concerns, it can't tolerate outdoor exposure the way plywood siding can. Louisiana-Pacific discovered this in the early & mid-'90s when it marketed Inner Seal, a brand of OSB siding. The resin-treated coating that was supposed to protect it from the elements failed, and the panels began to crumble. L-P spent tens of millions of dollars settling suits by homeowners whose siding disintegrated, leading to the ouster of chair & president Harry Merlo in 1995.

tropical plywood
Probably the most celebrated plywood cause has been the logging of rainforests in Southeast Asia, esp. Malaysia & Indonesia, to create a product that is thrown away after a short time. Lauan is a group of heavily used tropical tree species used to make plywood. Lauan plywood is used extensively in Japan, both for concrete forms and for cheap furniture, often discarded after a few years. It has also been a favorite of Hollywood set builders, who used to go through a quarter of a million sheets of lauan plywood a year. Some studios such as MCA/Universal & Paramount have recently shifted to ecologically sounder substitutes; others, such as Disney & Warner Brothers, have cut back significantly on their use of lauan. Indonesia & Malaysia remain the second & fifth largest makers of plywood in the world; Malaysia would place higher if the logs it exports for plywood manufacture elsewhere were included. In some parts of the tropics, such as the Amazon, most logging is a by- product of other economic pressures to clear land for ranching, or build mining roads. But in SE Asia, logging is the main force driving the clearing of the rainforest and the displacement of peoples such as the Penan of Sarawak in Malaysia, stories that are familiar to many Liberty Tree readers.

sustainable substitutes
The Rainforest Alliance operates a certification program called Smart Wood to distinguish sustainably harvested forest products which originate from temperate as well as tropical regions. Certifiers consider the entire management system of a forest in deciding whether to award their stamp of approval, from logging techniques to fair labor practices. For a fuller discussion of certification, see the Forests article In the Trenches.
Smart Wood recognizes at least 2 plywood suppliers. Plywood & Lumber Sales in Emeryville, CA (510.547.7257) offers top-grade cherry & red oak panels, in sustainably harvested veneer glued onto a core made of North Dakota wheat straw. These panels will sell to cabinetmakers for about $130 or so, compared with the $85 for a comparable run-of-the-mill panel. Wisconsin's Marion Plywood Corp. (715.754.5231) offers plywood made from the certified Menominee Tribal Enterprises hard maple, yellow birch and red oak.

A variety of panels made from post-consumer waste is available. Homasote is made from discarded paper, which is pulped then formed into boards. Homasote, which has been in use since 1916, comes in styles suitable for roof decking, subflooring, sheathing and interior design. Unicore is a similar product, which Universal Studios has just adopted for its set construction.

Out on a gravel road on the very edge of the Southern California megalopolis, I am sitting in the sunshine on a stack of freshly sawed boards with Mike Easterling. I'm here in Irvine because 2 things are occurring simultaneously in U.S. cities, one lousy, the other heartening. Both are happening in front of our eyes, although they are not easy to discern. I am referring to our essential regard for nature. Plus scary topics such as global warming, our brimming landfills, the loss of our rain forests, polluted water and rising energy demands. I am also thinking about our love of wood, in this case, prime softwoods & exotic hardwoods from the far corners of the world, the stuff to make floors and guitars and conference tables and paneled living rooms and patio furniture and salad bowls and 1,000 other fine things. Our topic is trees.

Cedar boards on which Easterling & I sit are part of a revolution. His San Marcos-based company, East-West Urban Forest Products, sells lumber salvaged from our frontyards, from roadway medians & city parks, trees uprooted by storms, trees that have reached the end of their lives, trees taken down to make way for development. For the last 15 years or so, a few farsighted people have begun to conceive of urban landscapes in a new way. They saw the forest in the trees. Now the idea is catching on, and it's about time. Scandalous waste is being transformed into entrepreneurial gain for the well-being of us all, and just in the nick of time.
The problem: Of 50 million tons of solid waste produced in California, 16% is so-called green waste from vegetation and 4% is wood. Municipal officials regard the wood/tree component as a drain on their civic budgets, all that tree trimming, storm cleanup and stump pulling that ends up in landfills. Under state mandate to reduce solid waste, city officials are increasingly turning away from replanting big trees in favor of smaller ones & shrubs. Incrementally, day by day, these decisions promise unpleasant consequences for city dwellers.

Big trees provide shade, which saves energy by cooling homes naturally (up to 20 degrees). They capture rainfall that otherwise courses over dirty streets and creates toxic storm-runoff problems. They scrub the air clean, dampen noise, beautify our neighborhoods and renew our connection to the cycles of nature. Eliminating big trees in favor of scrawny ones is presumed to be cheaper in the short run but costly in so many other ways. Easterling, with a background in furniture-making, is in the retail end of a movement out to prove that city trees can be managed as forests. They can pay for themselves and for the good of the environment, here and afar. "Our mission is to put the lumber from our urban forests to higher use," he says. "Every time someone buys urban wood, that's one less tree that has to come down in the rain forest."

He opens a gleaming wooden case. Inside are 36 rectangular samples, like tiles, of the most common commercial woods produced locally. California has the advantage of a favorable growing season and a long tradition of planting exotic trees in the cities, from gum to carob, from carrotwood to black acacia. These woods have the added cachet of sentimentality, as any woodworker could tell you. Each tree ring, each fancy twirl of figuring is part of our shared history, whether it ends up as an architectural accent in a home or a night stand in the bedroom. Prime hardwood fetches premium prices at specialty lumber yards. A board foot 1" thick by 12" square of silk oak imported from Australia could cost $7.50. That same species of tree, common to Southern California, has been ending up in landfills, or at best, as firewood.

Now, West Coast Arborists Inc., which does tree service for 100 municipalities throughout the state, is also becoming a lumber mill, using Easterling to market and sell the wood. "We've been disconnected from the things that trees bring to our lives," says California Forestry Dept urban specialist Eric Oldar. "To think of trees as potential commodities brings the idea of sustainability to our cities Trees are an essential part of the cultural nervous system of livable communities." With grants and loan of milling & drying equipment, the state is now coaxing along half a dozen projects to bring city trees to market, and similar urban forestry endeavors are underway elsewhere, although the yield in lumber is still only a tiny fraction of its potential. The goal is more trees, more shade, more rain absorption, cleaner air, more nature in our urban environment. As soon as city officials realize the payback potential from lumber, let's hope we see a planting boom.
Where do you live? I live in the forest. I live in Southern California.

ROSEBURG, OR   America's timber country: rolling green carpets sweep into mountains home both to 28 million acres of commercial forest and to the largest stand of old-growth timber in the world. Most people here in Douglas County have never thought twice about cutting a few trees, not surprising in a place where unemployment is at 11% and a third of the jobs left are linked to the forest. While demand for new logging continues to be heard in timber towns across the Pacific Northwest, it appears there is substantial public support for setting aside the stands of huge, old trees that have all but disappeared except for on the lush, rain-fed slopes of the western Cascades. When asked recently whether they favored an end to logging in old-growth forests on public lands, 63% of residents in resource-dependent areas such as Douglas County said yes. So did 70% of those in Oregon & Washington overall.

In what could be an important shift by the timber industry, Boise Cascade Corp., now known simply as Boise, announced last month that it would end all logging on large stands of old-growth forest. The company, largest purchaser of federal timber in the country, cited the dwindling availability of old trees, mostly due to environmental controls. "Less than 1% of the wood we use in our manufacturing operations comes from what most people would consider old growth," Boise spokesman Mark Moser said. "And the direction of federal forest policy management was to offer less & less old growth for sale. It was sort of an evolution that we got to, and we decided we might as well discontinue it altogether."

But conservationists say consumer pressure for products free of old-growth fiber also was a factor. "I think that what we've seen in the last 6 or 7 years is a shift in public sentiment. People see the converting of 800-year-old trees into 2-by-4s or copy paper as just being barbaric & unnecessary," said Rainforest Action Network Michael Brune. The conservation group has led a consumer drive against Boise & other firms to shut down logging on old-growth forests.

Though logging on public lands always has been controversial, at issue now are forests that may be anywhere from 150 to 800 years old, areas sometimes called "cathedral" forests, with towering, moss-draped stands of Douglas fir, hemlock and cedar. These trees are invaluable to the industry for making high-grade beams, doors, moldings and telephone poles. The federal government has shielded about 21 million acres of the 24 million acres of federal forest land in the Pacific Northwest from logging including 7.4 million acres set aside as old-growth reserves. But at least 440,000 acres of classic old growth, and another 600,000 acres of younger but still "mature" forest, are within areas scheduled for logging over the next few years under the NW Forest Plan brokered by then-President Clinton.

Most of this land is in the Umpqua National Forest in & around Douglas County, as well as the Mount Hood, Willamette, Rogue River and Siskyou national forests of Oregon and Washington's Gifford Pinchot National Forest. In California, about 10% of the Sierra Nevada forests are old growth; some stands also remain along the state's northern coast. Much of that land is scheduled for logging in coming years. Conservation groups say that with all but 10% of the historic Western rain forest already gone, it is important to save what is left.

"This is America," said Northwest Ecosystem Alliance Mitch Friedman , one of 13 groups that launched campaign to win congressional support for end to logging on public old-growth forests. "We don't hunt whales. We don't spray DDT. And we shouldn't log old growth." A panel of Northwest economists recently joined a group of environmental scientists in calling for old-growth protection, pointing out that tourism & other recreational use is playing an increasing role in the regional economy. Logging on federal lands already has declined to just 7.5% of all logging in western Oregon & Washington, they noted, and only 3.9% of logs processed from 1990 to 1996 were more than 100 years old. "While elements of this transformation were forced on the industry, it nonetheless resulted in a fundamental restructuring," the economic analysis said. "The employment, income and price impacts of protecting our remaining old forests are likely to be very small in percentage terms."

Timber industry leaders admit some public opinion leans toward old-growth protection, but they contend few people want all federal forest land locked up. Most, they say, would support a balanced approach that allows logging for fire protection, disease control and as a renewable source of lumber.

"I think the public probably wasn't asked the right questions," American Forest Resource Council president Tom Partin in Portland, OR, said of the recent polling. "They should have been asked, 'Do you know how much of the national forests are already set aside? Do you understand over 50% of the national forests are at high risk due to fires because of the overcrowding?' I think if the questions were addressed in the right context, you'd probably get a different response."

The poll conducted by independent firm of David, Hibbits & McCaig included 600 registered voters in Washington & Oregon. It asked if they would support protection of old-growth forests on public land from logging, as well as at what age forests should be considered old growth. Overall, 70% said they strongly supported or somewhat supported protection, while 25%% opposed it. Douglas County commissioner Doug Robertson conceded conservation message has made inroads, even in a region that once called itself the timber capital of the world. "Over the course of the last 12 to 15 years, the environmental community has done a very good job of engaging the public on an emotional basis relative to old-growth forests, without telling the complete story in terms of management . . . that the buildup of fuel on the forest floor has resulted in the destruction of old-growth forests by fire," he said. "Do you want to protect old growth? Do you want to protect the harp seal? Do you want to protect the whales? Well, sure. But it needs to be looked at in a lot of depth, and people seldom do."

The old-growth protection campaign has been controversial, even in the environmental community. Some conservationists fear that legislation being drafted by Sen. Ron Wyden (D-OR.) will protect old growth at the expense of logging on other forests. "We really need to stop logging on national forests [entirely]. Just protecting the old growth isn't enough," said John Muir Project Chad Hanson. Wyden emphasized that any legislation would have to include "a substantial & appropriate thinning program" to manage other forests against fire & disease. In Douglas County, 70% of timber that feeds mills now comes from outside the county. Court restrictions have halted most old-growth logging here. "We can design forestry to produce old trees on a very regular basis," said D.R. Johnson Lumber Co. resource manager Jerry Keck "People forget that trees grow. We cut them because it's a renewable resource."

The Umpqua River valley east of Roseburg is blanketed with private tree plantations, giving way to the majestic old-growth stands of the Umpqua National Forest. The Diamond Lake district high in the hills, where Boise a few years ago completed a major logging project, is pockmarked with clear cuts. In a recent flight up the valley, Cascadia Wildlands Project James Johnston pointed down to the jagged, multicolored hues of old growth standing among the homogenous stretches of logged and replanted forest. Boise has pledged not to log any old-growth trees in stands of 5,000 acres or greater. But very little of the old growth left in this valley is in tracts that large, Johnston said. "The only kind of old-growth that's going to be protected [by the company's recent decision] is the kind . . . that doesn't exist anymore," he said.


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