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Madison, WI 53726-2398
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Title: Estimating Janka Hardness from Specific Gravity for Tropical and Temperate Species

Source: USDA Forest Service, Forest Products Laboratory, Research Paper, FPL-RP-643, 2007

Author(s)Michael C. Wiemann; David W. Green

Publication Year: 2007  View PDF »

Category: Research Papers

Abstract: Using mean values for basic (green) specific gravity and Janka side hardness for individual species obtained from the world literature, regression equations were developed to predict side hardness from specific gravity. Statistical and graphical methods showed that the hardness-specific gravity relationship is the same for tropical and temperate hardwoods, but that the relationship for softwoods is different from that for hardwoods. As expected, the relationship for green wood is different from that for wood at 12% moisture content.

Keywords: Janka hardness, specific gravity, temperate hardwoods, tropical hardwoods, softwoods

Publication Review Process: Informally Refereed (Peer-Reviewed)

File size: 578 kb(s)

Date posted: 07/29/2011

This publication is also viewable on Treesearch:  view
RITS Product ID: 584
Current FPL Scientist associated with this product
Wiemann, Michael C.

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