11 Nov., 1918. 



Apple C'uHure in Victoria. 



649 



Annually the corrugations or sectoral inequalities in the wood of 

 affected trees become more pronounced in consequence o£ the high and 

 increasing ratio of growth in the raised parts as compared with the 

 depression. When the stems become badly affected, they are contorted 

 into many shapes, but the most serious condition exists when the wood 

 becomes flattened. While in this state the trees are liable to break 

 down with the weight of their fruit, or they may have their stems 

 broken by the wind, or the tree may be blown down bodily. 



The illustrations in Plate 179 will enable the reader to better 

 understand how this impediment m the Gravenstein wood develops. 

 These cross-sections were taken from the stem of a badly affected 



Plate 178. — Sections of affected wood from a Gravenstein tree, 

 three years old. 



fourteen-year-old tree. They were 10 inches apart, and the corruga- 

 tions irregular, as the illustrations shoAV. When the stems and branches 

 make nonnal growth, the annual rings of wood, when viewed in cross 

 sections, describe almost perfect circles. The wood of every sector of 

 each annual ring is of uniform development and equi-distant on the 

 medullary lines from the pith. Now compare the cross-sections in the 

 illustration with the formation described. The inner circle in Fig. 1 



