Mechanical, Physical, and Machining Properties of Black Walnut From Indiana and Missouri


  • David R. Schumann


<i>Juglans nigra</i>, wood quality, specific gravity, volumetric shrinkage, hardness, toughness


The relationships of the anatomical characteristics and physical features of black walnut to the machining and mechanical properties were investigated. The influence of geographic location, site quality, and growth conditions on these properties was also examined. Machining properties of black walnut were satisfactory regardless of locality, site, growth rate, and anatomical characteristics.

Specific gravity influenced the machining and mechanical properties of black walnut more than any other feature. Specific gravity increased slightly with an increase in growth rate.

Indiana-grown black walnut heartwood contained less extractive material and conscquently shrank more than Missouri-grown wood. Good sites, regardless of location, produced tougher wood than poor sites.


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Research Contributions