FOREST TERMINOLOGY 77 



Disengagement cutting or felling. See Intermediate cuttings. 



District, v. To make a subdivision of a forest into units on map or ground. 

 Syn. ; divide. 



District, n. An administrative subdivision. See Subdivision. 



Dominant. See Crown class. 



Duff. See Forest floor. , 



Empirical yield table. See Yield table. 



Equalization period. The period during which it is planned to attain approximately 

 normal stock conditions. 

 G., Einrichtungszeitraum. 



Estimate, v. To determine the approximate contents of trees or stands of timber. 



Estimate, n. An approximate determination of size, contents, value or anything 

 else ; more specifically of the volume of a tree or stand. 

 Syn.: cruise. 



Even-aged, Applied to a stand in which only small age differences appear, differ- 

 ences varying with the average age of stand. In young stands, age differences 

 should not be more than 10 or 20 years; in mature stands, not more than 30 or 

 40 years. 



G., gleichalteriger Bestand. F., peuplement uniform. 



Expectation value. See Value. 



Exposure. See Aspect. 



Factors of locality. See Site. 



Fail spot or place. A place where natural or artificial reproduction has failed. 

 G., Fehlstelle. F., vide. 



Felling. Syn. : cutting. The term felling is preferred by the collating committee 

 for its better terrn quahty, especially where substantive meaning is prominent 

 See under Cutting. 



Felling age. See Rotation. 



Felling area. An area on which the trees have been cut or are to be cut. 



Felling budget. See Cut. 



Felling cycle. The planned interval between fellings or cuts on the same forest 

 area. See also Reproduction, Selection method. 

 Syn.: period of return. 



Felling plan. See under Working plan. 



Felling series. An aggregation of stands into a proposed or actual sequence of 

 feUing areas, the object being a distribution of felling areas for administrative 

 reasons or to secure a final satisfactory distribution or location of age classes, 

 especially to avoid damage by windfall and insects due to uniformity of stand and size 

 of felling area. It is intended to interrupt a regular sequence of age classes. 

 Syn.: cutting series. 

 G., Hiebszug. F., s6rie de coupes. 



Final cutting. See Reproduction, Shelterwood method. 



Final yield. See Yield. 



Financial maturity. See Maturity. 



Financial rotation. See Rotation. 



First growth. See Old growth. 



Forest, n. In common usage, a large tract of land covered with trees; more exactly, 

 a tract of land, more or less extensive, covered more or less densely with trees of 



