Correct option is B
Upsets:
Upsets refer to defects caused by improper handling or mechanical damage, such as crushing of fibres, usually during felling or transportation of timber.
The explanation provided in the statement is incorrect as it describes foxiness rather than upsets.
Foxiness:
Foxiness refers to discoloration of wood caused by fungal attack due to improper ventilation or prolonged storage in damp conditions.
It is not related to crushing of fibres running transversely.
Star Shakes:
These are radial splits originating from the centre of the log and extending outward.
They are widest at the circumference and diminish towards the centre.
Cause: Star shakes are usually caused by excessive heat or frost during the growth of the tree.
Heart Shakes:
These are cracks or splits that start at the heart (centre) of the tree and extend outward, diminishing in width towards the outer circumference.
Cause: Heart shakes are formed due to shrinkage stresses in the core of the tree during seasoning or natural growth.
