SYLVICULTURE 



products obtained and from the willingness of the owner to embark 

 in sylvicultural investments, 



a. Investments in permanent means of transportation; 



b. Relative safety from forest fires; 



c. Time. 



Wherever the woods emerge in a decrepit condition from the 

 primeval stage after reckless lumbering, heavy fires, unlimited 

 pasturage, there the adoption of a system will be found necessary 

 after scores of years breaking entirely with the past and raising, 

 after thorough destruction of the past growth, by artificial means 

 a new crop of valuable species. 



Large, continuous clearings badly resist reforestation like the 

 prairies, although on a smaller scale. Extensive, even-aged woods 

 form '"incubators" for disastrous diseases; suffer from snow, storm, 

 drought, and frost. On the other hand, their management is greatly 

 facilitated, so that reinforcing, cleaning, thinning, regeneration and 

 utilization are much cheapened. 



B. Selection of form by the forester. 



I. The primeval forms of high forest found by the forester 

 usually appear unretainable. Whatever the case be, the first stroke 

 of the axe is sure to remove the mature and hypermature trees, the 

 preponderance of which belongs to the character of any primeval 

 form. 



However, when transforming primeval woods into cultured 

 woods, the forester should endeavor to retain as much as possible 

 the form originally sanctioned by nature. Such retention is the 

 safest way to sylvicultural success. Still, it usually necessitates 

 heavy investments for permanent means of transportation, and where 

 the owner is unwilling to make them, cuttings by compartments or 

 by strips are required, which in turn lead to the adoption of the ad- 

 vance growth type, shelterwood type, or cleared type of n. s. r. 



The strip form, as mentioned elsewhere, seems to be particu- 

 larly well adapted to meet American needs. 



II. The culled forms of high forest must be retained by the 

 forester in the compartment, group or selection form first en- 

 countered, unless the culling has been particularly light. Improve- 

 ment cuttings are not apt to change the form of the forest. Where 

 artificial reinforcing is resorted to, the forest will gradually develop 

 even-aged forms. When after heavy culling the average growing 

 stock per acre is badly reduced, then forms allowing of short rota- 

 tions are indicated, so especially selection forms and standard forms. 

 Frequently in such cases, the high forest is abandoned, and the 

 coppice forest is resorted to. 



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