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CORYLACE.E. 



the stem we have always found attended by injurious 

 effects, but to a much greater extent 

 when performed during the dormant or 

 winter season than when the tree was in 

 leaf, and its vitality in full action. If 

 performed during the first-named period, 

 in addition to a rapid taint or incipient 

 decay of the surface of the wound, we 

 have generally observed that the bark at its lower angle 

 lost its vitality and began to decay, thus enlarging the 

 wound to a considerable extent downwards, as shown 

 in the figure, and exposing in addition to the space occu- 

 pied by the branch, a large surface of the stem to the 

 action of the air and moisture. 



This, however, rarely takes place in a healthy tree when 

 the branch is taken off during summer, or immediately 

 after the tree has expanded its leaves, for its vital functions 

 are then in full activity, and it has already begun to ela- 

 borate and deposit its layer of alburnum 

 or young wood which immediately be- 

 gins to form around the edges of the 

 wound as shown in the figure, (where 

 the white ring represents the recent- 

 ly-deposited wood,) and, continuing to 

 advance upon it, has generally by the 

 end of summer so far covered it as to protect the lower 

 angle from the effects of cold and moisture. 



But the Oak in mixed plantations, or grown in mass, 

 does not require the artificial pruning that Pontey and 

 others have advocated, to give it length and cleanness 

 of stem, to qualify it when mature for plank timber ; in 

 such situations it must necessarily make every effort to 

 keep pace with the growth of the other trees around to 



