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“Figure” is a general term referring to the visual surface effects which result from the infinitely varied porous structure of each tree or, in fact, section of each tree. Obviously, the general appearance is affected by the manner in which the log is cut into veneer (i.e. flat cut, quartered, etc.) but the basic cross figure or curl types remain dominant, no matter how the log is cut. There are two general figure categories, (1.) grain figure, resulting from various cuts in relation to the annual growth rings (ex. 1,2,3,) and (2.) crossfire figure, which is a distortion of the normal structure and, as the name implies, result in figure markings of various types across the grain . (ex. 1,2,3,4)
BIRDSEYE - There are many theories concerning the generation of “birdseye” figure or appearance which occurs almost exclusively in Hard Maple (Acer saccharum) growing in the Upper Peninsula of Michigan and, of much less significance, in a similarly narrow latitude east to the Maritimes. It is said that birds peck the surface (necessarily to the cambium layer) if the trunks of the relatively limited number of “chosen” trees, and to varying degrees, maybe in search of “bugs” or possibly seeking the Sugar Maple sap. These variously scattered irritants to the normal growth layer heal with spotty distortion, are cut across and revealed in the veneer as birdseye figure. Obviously, the more “scattered irritants” the more “spotty distortions”, and therefore the more desirable birdseye effect. (example)
BLISTER - A decidedly uneven contour of the growth rings brings about blister figure when the log is rotary cut and the straight knife passes across these contour variations. The veneer, while smooth, appears to be covered with blisters. The only difference between blister and quilt or Pommele´ is size of figure. Occurs mostly in West African redwoods such as Khaya (Mahogany) Sapeli and Makore. (example)
BROKEN STRIP - This strip effect develops only in quarter slicing veneer, usually includes some end wood character, and it appears that the strip figure runs down under the surface and then out again, more of less “broken”. It occurs most commonly in the large tropical redwoods but also to some degree in a broad range of tropical species. (example)
BURL - A burl is a wart like growth, probably caused by some injury to the growth layer. In the process of “healing”, there may be very abnormal growth and accumulation of undeveloped buds to eventually form this burl, which may very in size from a few inches (of no veneer value) to a tremendous, somewhat oval growth weighing as much as two tons. Burls figure results from rotary cutting this growth, and the general appearance is a close arrangement of many small “eyes’ with much distorted grain appearance intermingled. Burls are common mostly to a few species, including Walnut, Myrtle, Redwood (California, that is), Elm (European), Madrone, Ash and Mappa (European Poplar). (example)
BUTT - Butt figure results from half-rounding sections of the stump wood. Where the roots from into the solid stump, there is considerable distortion into wavy ripple marks. Of course, there is always the distorted grain figure, along with greater or lesser amounts of the wavy cross figure. American Walnut is the principal species which lends itself to production of Stumpwood Veneer. The U.S. market values Walnut Butt Veneer (other factors being equal) by percentage of sheet showing the Butt cross figure (example). (Reference Walnut, French, and Walnut, English)
CLUSTER - The cluster figure results from cutting half round veneer from the trunk of certain trees in which it is characteristic . It is some variation of scattered clusters of burl figure, intermingled between the clusters. Often the muscle figure is very strong around the clusters and fades out to almost plain areas between. This is most common in Myrtle and West Coast maple, Claro Walnut and Ash (European). (example)
CROSSFIRE - This is a general term often applied to all the various types of figure markings across the grain. However, it most likely refers to a type such as (example) In the German trades they call it “Blitzen” (lighting).
CROTCHWOOD-FEATHER - A crotch block (flitch) is cut from that portion of the tree where it forks into tow limbs, like a “y”. Where the grain forms together at the “crotch”, there is great distortion of fibers in interlocking growth. At the center of this crotch block is the concentration of this effect, and when veneer is sliced from this portion, a feather of plume or flame effect is obtained. It is of interest to observe that crotch veneer, when used in a vertical position on furniture, is almost always used upside down from the way it grew, and that is the way it is shown (example ). Turn the image upside down and visualize the two limbs of the tree projecting up to the right and to the left. Crotchwood growth suitable for veneer is by far most common to Khaya (African Mahogany) and the to Western Hemisphere Mahogany, Walnut, and occasionally a few other species. (example)
CURLY - Results from distorted growth of fibers in the trunk of the tree that gives a wavy or curly appearance in the veneer. This figure is usually most common in Birch. No good illustration of the figure appears herein, but a combination shown: (example 1,2) this provide a good example.
ENDWOOD - The effect of the pore or fiber direction being perpendicular, or nearly so, to the surface of the veneer, in contrast to more common formation where fibers are, in general, parallel with the surface and length of the veneer. Endwood is most common, and is responsible for much of the figure effect in crotch and burl veneer as well as strong mottle and broken strip. (example 1,2,3,4,5,6,7)
FIDDLEBACK - This figure is somewhat similar in growth and effect to the curly type and is often referred to as “Curly”. However, “Fiddleback” refers only to a small roll appearance (example) The name is derived from the fact that, historically, this figure in Maple has been highly prized for making fine violins (fiddles). Not common, but occurs occasionally in Maple, Khaya, Makore, Douka, Black Bean, Koa, English Sycamore.
FLAKE - Flake figure is developed only in those species which have very heavy medullary ray growth (example). When the saw or knife cut is directly on or near to the radial, it is close to parallel with the medullary ray and therefore passes in and out of the uneven growth to develop the flake effect. (graph example see Fig 4)
FLAT CUT - A grain figure resulting from slicing across a half or quarter of a log; tangential cut. (graph example see Fig 3 & 5 ) This results in the oval or loop grain effect in the center of the sheet of veneer with straighter grain along the edge (example)
GHOST FIGURE - Term generally applied to any cross figure which is not at all prominent, but is noticeable from certain angles and may show up to some extent under finish.
KARELIAN BURL - This is an individual characteristic (not really a burl growth) of Birch growing in some areas of Karelia, for practical purposes Finland. (example)
KNOTTY CHARACTER - Sound knots appear in only a portion of veneer (or lumber) cut and in intermittent fashion. (example)
MOTTLE - This is another type of cross figure. The effect of broken up cross markings, intermingled with strips, is generally referred to as mottle. Broad cross markings, broken by variations in strip, produce a block or patchy effect, known as block mottle, (example) and a very small, fine figure is referred to as bees-wing-mottle ( example) .Block mottle figure occurs more often in Khaya or Makore while bees-wing-mottle is more common to Sapeli, Bubinga, Satinwood, Black Bean.
NATURAL - A general descriptive term to indicate surface appearance of knots (sound or fill-treated) and all character markings inherent in the respective hardwoods. “Natural” is to hardwoods (i.e., Natural Walnut, Natural Butternut, etc.) as “Knotty” is to softwoods (i.e., Knotty Pine, Knotty Cedar, etc.). (example)
OLIVE ASH - This name is applied to the heartwood of both American and European Ash where the color is bright tan with characteristic olive markings. The rare log so develops and the name is one of description rather than classification. (example)
PLAIN STRIPE - This is a result of quarter slicing, where porous structure is formulated most normally parallel with the length of the veneer and with a minimum of distortion. A straight, uniform, stripy effect results. Common in almost all timber with a wide variety of character. (example 1 & 2)
POMMELE´ - This is a French word translated as “dappled” or “mottled”. As commonly applied to the appearance of certain veneers, it is then somewhat of a misnomer in pure translation because it actually denotes a large “blister” or “quilt” figure usually in West African redwoods such as Khaya, Makore, Sapeli and Bubinga. (example)
QUARTERED - The sliced cut of a log as near to true radial as possible, which results in the stripe effect of one type or another, as mentioned herein. (see graph Fig. 4 ) (example 1,2,3,4)
QUILTED - A very uneven or wavy interlocking contour of the growth rings is evident on the outside of the log as a more or less even but very “bumpy” surface. Rotary or halfround cutting along this surface produces veneer with a quilted effect of continuous seashell overlay surface. It is interesting to note that a very similar condition or appearance is known as quilt in Maple (quilted Maple) Pommele´ in African redwoods (example) and Peanut Figure in Japanese Ash (Tamo).
RIBBON STRIPE - This is a result of quarter slicing the log and actually is between broken strip and plain strip. It gives the general appearance of a ribbon slightly twisted. (example ): show stuff from p. 60)
RIFT - This description of figure or grain character is most commonly applied to veneer or lumber cut from those species having a heavy medullary ray growth. It is now almost synonymous with White Oak, in view of the popularity of Rift White Oak veneer. The effect in veneer is straight grain and no flake, produced by a cut near enough to radial to be across the growth rings and yet, at all times, enough off the true radial cut to avoid any direction of the cut parallel with the medullary ray. The most practical way of effecting this result is by a slight curve, accomplished by producing Rift Oak on a veneer lathe. (see graph Fig. 6) (example)
ROLL FIGURE OR HERRINGBONE - In description of Fiddleback Figure, reference is made to “small roll appearance”. While fiddleback figure is usually fairly horizontal to the length of the veneer, roll figure will appear as larger rolls or twists running more likely at some diagonal degree. Thus, when book matched, the “herringbone” description evolves (example).
ROTARY - A method of cutting in which the log is placed on a large lathe and turned into the knife, so that continuous cut is made round and round the log, more or less parallel at all times to the growth ring, Result is a wild, variegated, grain effect. Except for Stumpwood, Burls, and certain figured logs for fine face veneers, (example) rotary cutting is used largely in commercial veneer production. (see graph Fig. 1)
WORMY CHARACTER - Under certain conditions worms or borers attack the log (seldom the living tree) to the extent that worm holes appear almost uniformly in sheet of veneer when cut. In that event a very pleasing effect may result. (example)
Pictures on the following pages are intended to illustrate a typical grain pattern and/or matching of the veneer and/or figure type without regard to species. Each species has its own character. Figure types are usually common to a few species.
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