. An annotated list of the important North American forest insects. Forest insects. DEFECTS IN TIMBER CAUSED BY INSECTS 15 of old dead and dying sna<!;s, sta<j^-headed trees, and trees badly fire- scarred. From 20 to 25 per cent of oak lumber may be wormy from this cause. A loss of 15 to 20 per cent of the product is considered low. Pinholes or wormholes one-eighth to three-sixteenths of an inch in diameter, few to many grouped in a given space, accompanied by a staining of the wood, or all more or less connected by irregular blackened streaks, in ^ V'i III 4 oak, maple, tupelo gum, beec
. An annotated list of the important North American forest insects. Forest insects. DEFECTS IN TIMBER CAUSED BY INSECTS 15 of old dead and dying sna<!;s, sta<j^-headed trees, and trees badly fire- scarred. From 20 to 25 per cent of oak lumber may be wormy from this cause. A loss of 15 to 20 per cent of the product is considered low. Pinholes or wormholes one-eighth to three-sixteenths of an inch in diameter, few to many grouped in a given space, accompanied by a staining of the wood, or all more or less connected by irregular blackened streaks, in ^ V'i III 4 oak, maple, tupelo gum, beech, and other hard- woods, are similar to those caused by the oak timber worm. This defect is caused by tenebrionid timber worms.^ The insect lays its eggs in the living tree near a scar or wound, and many larvae working to- gether excavate irregu- lar cavities and longi- tudinal burrows some- times a foot in length. This defect is fairly common throughout Pennsylvania, Mary- land, and Virginia and is classed as " worm- holes, no living worms or ; Although the losses can be greatly lessened by clean forest management, they are not preventable' fi-om the lumberman's standpoint. PINHOLE DEFECTS FORMED IN WOOD AFTER THE TREES ARE FELLED; A PREVENTABLE LOSS Pinholes in felled timber are similar to those caused in living trees by ambrosia beetles and timber worms. Such holes are less than one-eighth of an inch in diameter and open, either darkly stained or unstained, or with dark streaks in the surrounding Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Craighead, Frank C. (Frank Cooper), 1890-; Perry, George S; Snyder, Thomas Elliott, b. 1885; Hopkins, A. D. (Andrew Delmar), 1857-1948; MacAloney, Harvey John, 1896-; Graham, Samuel Alexander, 1891-; Peirson, Henry Byron, 1894-; Herrick, Gle
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Keywords: ., bookauthorhopkinsadandrewdelmar, bookcentury1900, bookdecade1900
