APPENDIX 331 



Shelterwood method. See Reproduction method. 

 Shoot. See Tree class. 

 Silvical. Pertaining to silvics. 



Silvics. 1. A branch of ecology that treats of the life of trees in the 

 forest; forest ecology. 



2. The life history, requirements, and general char. I of a 



forest tree from the point of view of silviculture. 

 Silvicultural characteristics. See Silvics (2). 



Silviculture. The art of producing and tending a forest ; the application 

 of the knowledge of silvics in the treatment of a for. 



G., Waldbau, Holzzucht. F., Sylviculture. 



Single tree method. (Obs.) See Reproduction (Selection) method. 

 Site. An area, considered as to its physical factors with reference to 

 forest producing power; the combination of climatic and soil conditions 

 of an area. See Site class. 

 Syn.: locality, physical type. 

 G., Standort. F., station. 



Site class. A designation of the relative productive capacity or quality 

 of different sites with reference to the species employed; the volume 

 or the height produced at a given age being used as standard for classi- 

 fication. In Europe five classes, in the United States often only three 

 classes are differentiated, designated by Roman numerals, quality I 

 representing the most productive site class. 

 Syn. : quality of site. 

 G., Bonitat. F., qualite du sol. 

 Slit method. See Forest planting. 



Slope. The gradient of the land surface. In forest description, the fol- 

 lowing terms are used to define the slope, each of which has its equiva- 

 lent in percentages of the horizontal distance and in degrees: 



Level = o- 5%= o- 3 



Gentle = 5- 15%= 3~ 8 

 Moderate = 15- 30%= 8-16 

 Steep = 30- 5o%= 16-26 



Very steep = 50-100% = 26-45 

 Precipitous = over 100% = over 45 



Snowbreak. The breaking of limbs of trees by snow. 

 G., Schneebruch. F., bris de neige. 



