ESTABLISHING FORESTS BY PLANTING 371 



with which the wounds heal. Most species of evergreen broad- 

 leaved trees have poor recuperative power after injury and con- 

 sequently suffer severely from pruning, as is the case with 

 rhododendrons and laurels. Among broadleaved species, willows, 

 poplars, oaks, alders, chestnut, mulberries, elms, and maples are 

 fairly resistant to pruning due to their recuperative power after 

 injury. Beech, birch, walnut, cherry, and ash are much less 

 resistant. 



Although conifers, as a rule, are slow to recuperate after prun- 

 ing, there are a number of exceptions. Larch withstands pruning 

 fairly well, while most species of cedar, cypress, and juniper with- 

 stand severe pruning without injury. When trees are planted 

 on fertile, moist soil they suffer less from pruning than when 

 planted under more unfavorable conditions. 



14. Other Factors which Influence the Quality of the 

 Planting Material 



There are a large number of factors in addition to the above 

 which determine the quality of various classes of planting mate- 

 rial. Success in planting depends very largely upon the selection 

 of planting material from the standpoint of its vigor and growing 

 power. In the inspection of stock to determine its quality, spe- 

 cial attention should be directed toward the relative proportion 

 of root to shoot. In general, the larger the root system in propor- 

 tion to the shoot the more vigorous the plant and the greater its grow- 

 ing power. So also the more compact the root system the better 

 the plant. A plant with a rambling root system and few fibrous 

 roots, as is likely to be the case when grown on sterile, sandy soil, 

 is of poor quality. The chief advantage of transplants over 

 seedling stock of the same size is due to the more compact and 

 fibrous root system of the latter. The shoot should be neither 

 too slender nor too thick. Over-slender plants are weaklings and 

 should never be planted. They usually arise from overcrowding 

 in the nursery or, in the case of wild stock, from excessive shade. 

 Plants that are abnormally short and stout arc liable to be dis- 

 eased and should be discarded. The buds should be well devel- 

 oped and, in the case of coniferous stock, the foliage should be 

 healthy. Plants in which the foliage is dwarfed and yellow should 

 not be used in planting operations. 



