AMERICAN SYLVICULTURE 



fire-scalded Oaks or Hickories, bent and low crowned; wolfs of 

 Yellow Pine; pretentious Dogwoods or Halesias and so on. 



C. Improvement cuttings improve the prospects of the over- 

 wood, remove undesirable members of the overwood and regulate 

 the number of the constituents forming an age-class of the over- 

 wood. " The normal cuttings in the overwood ai-e improvement 

 cuttings." 



In semi-normal woods, the oldest class of the overwood is 

 entirely removed. Class II is reduced to the former membership 

 of Class I; Class III is reduced to the former membership of 

 Class II, etc. It stands to reason, that the least desirable mem- 

 bers of a class should be thus removed. In semi-normal woods, 

 the improvement cuttings take place at the time at which the 

 underwood is ripe for coppicing. 



The improvement cutting yields timber of all sorts and of all 

 sizes obtained from the various age-classes. 



The improvement cutting does not regularly intend to help 

 regeneration. Frequently, of course, the stumps of trees removed 

 by the improvement cutting form sprouts partaking in the coppice- 

 tier. 



D. Pruning: Dead branches of the overwood trees might be 

 removed to develop timber clear of dead knots. 



Live branches of overwood trees formed low on the bole are 

 removed to lessen the intensity of the shade to which the under- 

 wood and the seedlings imbedded therein are locally subjected. 



The members of the overwood, owing to their free position, 

 are apt to form and retain heavy branches. The act of pruning 

 in coppice under standards corresponds with that described in para- 

 graph LXIII for high forest. 



The coppice is pruned only in rare instances, f. i., for the im- 

 provement of oak tanbark. 



E. Thinnings are sometimes indicated in dense coppice in order 

 to increase the food and light supply of the youngest age-class of 

 overwood imbedded in the coppice; or in order to increase gradually 

 the air space surrounding the members of that class, so as not to 

 subject them to the shock of sudden exposure at the time of cop- 

 picing; or to obtain the ends of Par. LXII. A., especially where 

 the overwood classes appear in groups; or to improve the quality 

 and the quantity of the bark in tanbark coppice. 



In all cases, the thinning must yield a surplus revenue. 



186 



