80 A MANUAL OF FORESTRY. 



instance, where wet swampy spots alternate with dry 

 parts, or where rocks are scattered over the area ; nor 

 is it necessary on small blanks scattered over already 

 existing woods. 



The comparative merits of the three principal forms 

 of regular distribution have been much discussed. The 

 triangular form allots to each plant the most regular 

 growing space, since every plant is equi- distant from its 

 neighbours ; this favours an even development of the 

 trees. It admits of a greater number of plants per 

 acre, and produces the greatest quantity of material ; 

 the saplings also clear themselves more readily of 

 their lower branches. On the other hand, it is more 

 troublesome to lay out, and more expensive than the 

 two other forms. 



Line planting has the disadvantage that the cover 

 overhead is somewhat later established, that the sap- 

 lings develop stronger branches on two sides than in the 

 direction of the lines, which may be accompanied by an 

 eccentric shape of the stem. On the other hand, it 

 admits of the most complete utilization of the ground 

 between the lines, and facilitates thinnings and the 

 removal of the material. 



On the whole, these advantages and disadvantages are 

 not of much importance, because after the early thinnings 

 the three forms stand practically on the same footing. 

 Many foresters prefer line planting to the two other 

 forms, because it is easiest to carry out, and perhaps the 

 cheapest. Others prefer the square form; while the 

 triangular form is perhaps less frequently chosen. 



The marking of the planting spots is done with two 

 lines (or chains), the so-called directing line and the plant- 



