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Long prized by woodworkers for its distlnctl figured pattern,bird's-eye maple reqwf;xes sharp tools and (#. defttouch t() shape and smooth successfulh'.in live parts of a tree normally heal over and disappear as newlayers of growth are added. In bird's-eye maple, the eyes grow radially,like spokes on a wheel, and they usually increase in size.Another theory attributed the eyes to undeveloped buds that remaindormant in the inner bark. If this explanation were valid, youwould expect the bird's-eyes to have dark cores and project in anoutward direction. But the cores are clear and the eyes grow asconical indentations pOinting inward, toward the tree's pith, asshown in the drawing at right.In the wake of this speculation, wood scientists began to system- .atically sort out clues to the bird's-eye mystery. First, they notedthat bird's-eye logs characteristically had dark stains or rottenheartwood. They also observed that figured trees were usuallyfound in a dense portion of even-aged stands; they were oftenunhealthy and deformed. Researchers determined that mapleswith the bird's-eye pattern took an average of 60 years longer toreach an IS-in. dia. d1an the normal, unfigured trees growing inopen stands. Regardless of how vigorous d1e trees' later growti1,old bird's-eye maples had narrow early-growth rings, typical ofyoung trees in a crowded stand that must fight fo r available light.Whatever the direct cause of bird's-eyes, suppression of the tree isprobably linked to their development.In the most recent effort to unravel the bird's-eye mystery, aresearcher at d1e U.S. Forest Service's Northeastern Forest ExperimentStation observed that a viral agent fit d1e known facts ofbird's-eye formation better than any hypothesis so far. However, todate, the experimental work has been inconclusive: Nature continuesto guard her secret well.Finding bird's-eye maple -The value and popularity of bird's-eyemaple, especially during the 1930s, prompted researchers to attemptto mass produce it using graftings of tissue from highly figuredtrees-without success. So bird's-eye aficionados cling to d1e fewavailable clues to guide them in their search. Bird's-eye has beenfound in trees as small as 2 in. in diameter, and tiny depressionsfound on I-in. maple saplings may be a sign of its beginning. Asthe tree adds layers of growth, these small depressions grow insize,ometimes extending through the bark. When present, andBird's-eye configurationBif:eJ's-e'fJ-es cause local distelifien in annual flings,aPleafting like spokes in a wheel.Bird's-eyes generallygrow larger from pointof erigin; distortedali/li/ual "ings createcOli/e-like structures.fJ?:Indentations incambium may ormay not extendtht'eugh and belie.v,ealed in bark.I>holo: Michele RussellI;winsk)': drawing: I.ee Ho\'January/February 1989 79