Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an injury, and in all probability does not of itself affect the properties of the wood. Certain rot-producing fungi impart to wood characteristic colors which thus become symptomatic of weakness; however an attractive effect known as spalting produced by this process is often considered a desirable characteristic. Ordinary sap-staining is due to fungal growth, but does not necessarily produce a weakening effect. COUNT 5
QSN1 What condition does an abnormal color usually indicate in wood? ANS1 diseased QSN2 What other property can you assume of wood that is diseased? ANS2 unsoundness QSN3 What causes the black checked pattern in the wood of western hemlocks? ANS3 insect attacks QSN4 What animals cause the reddish-brown streaks of color in hickory wood? ANS4 birds QSN5 What's the name for the pretty coloring effect caused in some wood by rot-producing fungi? ANS5 spalting