With the possible exceptions of cotton and concrete, there is scarcely a substance on earth that hasn't at least been tried as material for gunstocks. Stocks have been carved from ivory, cast of metals base and precious, molded from polymers, cobbled up from Lord knows what--even laminated from buffalo horn.

Wood, of course, is the most successful substance, but even then, the list of what's been tried isn't much shorter than a list of what's available--everything from oak to pine, birch to beech, mesquite to maple to myrtle to madrone, persimmon, pecan, holly, teak, mahogany, and such exotic African species as kokrodua, ekki, ebony, benge, bubinga, sifou, sapele, and some others of equally weird names. Most of these woods are perfectly serviceable for stocks, but ultimately, none can hold a candle to walnut. For gunstock wood, walnut is the king, the classic, the daisy, the pearl, the star.

Walnut is hard and strong, stable, lightweight, shock-resistant, flexible--probably courteous and reverent besides. It shrinks and swells less than almost any other wood. It's sweet to work, lovely to smell, delightful to handle, and takes a splendid finish. And walnut is without question the most extraordinarily beautiful wood on earth, ranging from the color of honey to the rich depth of chocolate-brown, often marked with smoky swirls and streaks of pigment from dark brown to black. The grain can be perfectly straight, elegantly swept, or a festival of waves, curls, mottles and motes, sunburst and fiddleback, as intricate as an opium dream. You can get lost in the texture of walnut.

WHICH IS NOT TO SAY THAT ALL WALNUT is created equal. Color and figure varies from species to species, tree to tree, even between parts of the same tree. Density, hardness, and working characteristics also vary, particularly from one species to another.

Walnuts belong to the genus Juglans, which comprises 40-odd species worldwide. Most are about equally desirable for cabinets, furniture, and veneer, but for gunstock wood, some are decidedly more desirable than others. Juglans regia, as its name suggests, is the aristocrat of them all. This is Old World or European walnut, variously called English, French, Spanish, Circassian, Turkish, Persian, Himalayan, or by some other name, according to where it grows. American black walnut, J. nigra, is endemic to eastern North America and was taken west by the pioneers.

California and Hinds walnuts--technically J. californica and J. hindsii but commonly called Claro--are native to the West. European walnut grows there, too, transplanted about a hundred years ago following failed attempts to raise it commercially in the East and South. This in turn led to a couple of man-made species, at least one of which is used for gunstocks. Bastogne is a hybrid cross between European and Hinds walnuts. Why it's named after a town in southeastern Belgium, I'm not sure, except that the Ardennes Forest region traditionally was a source of fine stock wood. (I doubt it has anything at all to do with the fact that American Brigadier General Anthony McAuliffe, surrounded at Bastogne by the German Army in 1944 and asked to surrender, replied simply, "Nuts!") At any rate, Bastogne walnut combines the characteristics of its parent stock--the intricate, predominantly fiddleback figure of Claro and the warm color of European.

Each species has its own peculiar physical identity. American walnut is densest and hardest of all. A one-foot cube of it, with moisture content at 12 percent, weighs 38 pounds, 5 pounds heavier than a similar cube of J. regia. In the standard hardness test, 1,010 pounds of pressure is required to embed a .444-inch steel ball to half its diameter in a slab of black walnut; 860 pounds will do the same to a piece of Old World wood.

STOCKS MADE OF BLACK WALNUT are sturdy, durable, and range from plain to nicely figured. The American arms industry turns them out by the zillion every year. Stockmakers, however, don't like black walnut as well as J. regia. Jack Rowe, an English stocker who now lives in Oklahoma, puts it this way: "It doesn't work so nicely as the French wood, and it doesn't smell as good, either."

Black walnut has at least one practical disadvantage besides. It's stiffer and therefore doesn't flex under recoil the way European walnut does. This isn't a problem with rifles, so long as the actions are solidly bedded and perhaps even fitted with recoil lugs, because rifle stocks usually are fairly chunky in the wrist. Nor is it much of a problem for a shotgun stock attached by a drawbolt. But black walnut worked to the slender proportions of a fine game gun and attached via the traditional tang screws is almost certain to develop a cracked wrist sooner or later--or a cracked head, a la L.C. Smith, because the wrist is unable to dampen the shock.

Claro often shows lovely color and striking figure, but it's the softest of all the gunstock walnuts. The open grain and comparatively pulpy texture make it the least suitable stock wood from a functional standpoint. Recoil stress can compress it over time and thereby loosen the fit between wood and metal. Sharply pointed, fine-line hand checkering is extremely hard to accomplish with Claro; about all you get is a crosshatch of fuzzy gouges.

Fiddleback figure, characteristic of both Claro and Bastogne, is certainly handsome to the eye, but it can be frustrating for a stockmaker. Since fiddleback runs across the basic grain of the wood, it often wants to chip rather than take a clean cut from an inletting chisel. Jack Rowe voices what seems to be a majority opinion when he talks about the working character of Claro and Bastogne: "You get bits and corners flying out when you're inletting; it's awful stuff. Awful stuff."

THE CLIMATE WHERE IT GROWS affects walnut profoundly. In cool climates, where the annual growing season is short, trees produce harder, denser wood, with growth rings more closely spaced. Consequently, the most desirable black walnut comes from the northern states--Minnesota, Iowa, New York, Pennsylvania. Climate is a function of altitude as well as latitude, and the finest of all gunstock wood traditionally has come from the Central Massif of France; from the Ardennes; from the Circassian region of the northwestern Caucasus along the Black Sea; and from the highlands of Turkey and Iran. Ironically, the one place that never has produced particularly good Old World walnut is England, though we persist in thinking of European walnut generically as "English."

Although they're the same botanically, Old World trees show certain regional characteristics, or so Greener insists. French wood, he tells us, is lighter-weight, more open-grained, and more richly colored than English wood. German and Swiss walnut is pulpy, soft, and gray; Italian wood heavy and bland in background color. Some stockmakers consider Old World walnut grown in California to be harder and more brittle than the same species grown elsewhere.

You can make a gunstock from any part of a walnut tree that can yield a proper-sized chunk--even a limb, although limb wood tends to be less stable (that is, more likely to warp) than wood from thicker parts. Stock blanks cut from sections where the trunk forks or where main branches meet the trunk often show an elaborate sunburst figure generally called "feathered crotch."

The best wood, however, comes from the base, from the root section up to about six feet above ground-level. There, especially where the roots join the trunk, the wood is densest and most beautifully figured. To describe a particularly handsome stock as "a fine hunk of stump" isn't entirely an exercise in folksy slang.

In order to obtain the root section, the business of harvesting a walnut tree is a matter of grubbing-up rather than cutting-down. In this country nowadays it's done by machine, especially on large-scale commercial plantations. In the old days, it was everywhere done by hand, and in many parts of the world, it still is. In regions where naturally grown walnut has been harvested for generations, suitable trees inevitably have become scarcer and their locations more remote, so that even now in the Near and Middle East, as elsewhere, machinery often is little more than a supplement to muscle and sweat.

WE THINK OF THE STOCKMAKER as the key figure in producing a fine gunstock. Actually, though, he is but one in a series of master craftsmen who contribute to the process and whose work must complement one another's if the results are to be fully successful.

The sawyer is the first of them. Once out of the ground and trimmed, the trees are taken to local sawmills where the bark is removed and the logs sawn into slabs about three inches thick. The sawyer's work is critical, because the angle at which wood is cut relative to the annular or growth rings of the log determines much of its ultimate appearance. Slab-sawing, in which the sawblade is basically parallel to the grain, reveals one sort of figure; quarter-sawing, in which the blade is angled across the growth rings, reveals another.

Both methods can produce lovely results, but by the same token, either method can turn a potentially gorgeous piece of wood into something as dull as cardboard. It all depends upon the tree and upon how skillfully the sawyer can read the grain before he cuts.

The marker, too, is a master of his craft. His job is to examine the rough-sawn planks and determine exactly how each one will be further cut into stock blanks. One of the marker's objectives is to get the maximum number of stocks out of each plank, but he must be concerned with quality and usefulness as well. Highly figured wood is attractive, but in practical terms, location of the figure is more important than looks.

A gunstock has to absorb a considerable amount of stress and strain, especially in the head, where it meets the metal, and in the wrist or hand, where a stock is thinnest. Since wood cracks along its grain, it's extremely important that the grain structure in the head and hand be such as to provide maximum strength and flexibility--and elaborate, curly grain does not meet that prescription. Ideally, the grain should run straight and parallel through the hand and head, especially in a stock attached by tang screws; the figure, all or most, should be farther back where it's displayed to best advantage and at the same time doesn't interfere with functional quality.

THE MARKER KNOWS ALL THIS, of course, and he patterns out each plank into blanks that show the best possible combination of beauty and strength. He may have to sacrifice a stock or two to achieve optimum quality, but the ones he does get will fetch a higher price in the end.

The marker also patterns his planks to avoid defects that sawing has revealed--cracks, wind-shakes, knots, and the like. And he tries to avoid sapwood, which is the softer, lighter-colored portion of the log nearest the surface. Sapwood is not necessarily inferior, and it can be stained to match the rest, but true best-quality stocks come entirely from heartwood, nearest the core of the log.

After the marker has done his work, the wood must be dried--either as planks or, more typically, as blanks. Freshly cut wood is full of moisture, both sap and water. Moisture content may, in fact, be as high as 90 percent, present both as free water and bound water. Free water is in the veins, pores, capillaries, and cell cavities, and it leaves quickly. Bound water is trapped in the interior structure of the wood itself and takes considerably longer to evaporate.

Walnut cannot be properly worked until the moisture content is down to about 12 percent. Otherwise, it will shrink and warp as it dries. Stock wood traditionally is air-dried, stored away in some protected place, and allowed to season for about six years before it's sold to gunmakers. Some gunmakers, in turn, dry it even longer.

In this century, some wood-merchants in France and Turkey have found a way of accelerating the drying process. Once the planks are patterned and cut, they seal the ends of the blanks, place them in a pit and steam them to drive out the sap. The remaining moisture apparently can be sufficiently evaporated in about a year.

American wood dealers generally prefer kiln-drying, arguing that it's the only way to achieve consistent, predictable results, and that it does so in minimum time besides. There are kilns and kilns, of course, and a wood-drying kiln is neither blast furnace nor bake-oven; rather, it's an enclosed chamber in which temperature, humidity, and airflow can be precisely controlled and where dehumidification generally takes place at less than 100 degrees Fahrenheit.

In either method, the objective is not only to reduce moisture content but to do so from the inside out, and to make it consistent throughout the blank. If free water is allowed to leave too quickly, the wood surface literally case-hardens, forming a hard, shriveled, cracked skin that effectively prevents internal moisture from ever getting out--or at least keeps it inside until a stockmaker removes the outer skin, at which point he's dealing with wet wood that will either warp or rust the metal parts attached to it, or both. Discovering fine lockwork pitted with rust from wood that was too moist does not make happy gun-owners.

Because stockmaking, like every other fine craft, has a highly subjective side, stockers disagree over the relative merits of kiln- and air-drying. American craftsmen seem about equally divided on the matter, but to a man, all of the Old World-trained stockmakers I know prefer their wood air-dried. They all say kiln-dried wood seems more brittle.

TRAINED AT PURDEY'S, David Trevallion has for nearly 30 years plied his craft in America. Specializing in best-quality English and European guns, he has worked with some of the finest walnut put on guns in the latter 20th century. He speculates that kiln-drying may remove more natural oil than air-drying does. "I notice it most in checkering," he says, "especially at 26 or 28 lines per inch or finer. Kiln-dried wood seems to chip more, while a properly air-dried piece will take 30 or 32 lines quite well."

One thing everyone agrees upon is that best-quality walnut is hard to come by. Apparently it always has been, since Greener, writing in 1910, remarks that "the amount of really fine wood available is limited."

Actually, it's sometimes a wonder that really fine wood is available at all, considering how much is lost to a whole range of ills, from disease and damage in harvest and hauling, to faulty sawing and improper drying. And then there's the matter of supply.

In climates that produce the best wood, walnut trees take 75 years or more to reach a size worth harvesting. And they've been cut for fenceposts and building lumber, burned as firewood, turned into military rifle stocks, and, especially in Europe, blown to splinters in two enormously destructive wars during this century alone. Gunmakers are only now beginning to feel the pinch from trees devastated during the 1914-1918 war; effects of the even greater carnage wreaked on European forests from 1939 to 1945 are still 20 years in the future.

Turkey and Iran continue to supply a fair amount, but for the most part, fine walnut stock blanks from the traditional sources are dwindling. Teyssier, the French company in Brive la Gaillarde that once supplied the London gun trade with wood that everyone calls the best of the best, has, I believe, recently closed down. Those who have the goods are selling ever more dearly--upwards of $700 per blank in this country (often considerably upwards) and ú1,000 or more in London, for top-quality stuff. A perfectly matched set of blanks for a matched pair of guns commands a premium price, $4,000 or more.

This is not to say that all the world's resources of walnut have been tapped. But such relatively untapped sources as Pakistan and South America and China, which probably has walnut trees by the million, are either unreliable or unavailable. Wood from yet other places--Australia and New Zealand, for instance--is for one reason or another less desirable. Australian walnut tends to be extremely heavy; New Zealand wood suffers an unusually high number of wind-shakes--cracks inflicted when the tree was young enough to be flexed and twisted by high winds.

THERE ISN'T MUCH USE WAILING over spilt milk or wasted walnut, but it seems a shame nonetheless that we don't truly appreciate something until it's hard to find. I don't bear furniture people any ill-will, but I do tend to see lost gunstocks in every fine walnut desk or table or cabinet. Worse yet, I've seen some rusty, beat-up old military rifles stocked with pieces of European walnut that could bring tears to the eyes of a dead snake.

On the other hand, a graceful game gun stocked with elegantly figured wood the color of honey and smoke is an almost tearful thing as well, but the feeling is different. It's a reminder that man and nature aren't always at odds, that sometimes, when human craft and the artistry of nature coincide, the result can take hold of your heart.