According to the number of variables

  1. Single Variable (dbh) : The volume tables show average volumes of trees by diameter classes. Since height varies in the same diameterin different localities, such volume tables can not be used for extensive areas.
  2. Two variables (dbh and height) : As trees of same diameter may have different heights and different volumes in different localities, volume tables based on two variables, are applicable to larger areas. Thus, these volume tables give volume of trees by diameter classes as well as height classes. More accurate than single variable.
  3. Three variables (dbh, height and tree form) : Such volume tables are called the form class volume tables.Though these are more accurate, these are expensive and difficult to prepare and inconvenient and time consuming intheir application.

According to the scope of their application

  1. General Volume Table: These are based on the average volume of trees growing over a large geographical area. Applicable to wider range of distribution of species. These tables are usually based on two variables, dbhand total tree height. These tables are used for deriving local volume tables.
  2. Regional Volume Table : These are compiled from measurement of trees growing in a region and therefore have a limited application when compared to general volume tables.
  3. Local Volume Table: Generally based on one independent variable, i.e. dbh (ob). These tables are compiled from the measurement of tree growing in restricted locality. These are either prepared directly prepared from field data or derived from general volume table, either by graphical equation.

According to the outturn given by them

  1. Standard Volume Table: These tables give separately the estimated outturn in the form of standard timber, i.e. From ground level to the limit of the portion of tree stem or branch where diameter is 20 cm. measured overbark, and small wood ,i.e. volume between diameterlimits of 20 cm and 5 cm both measured overbark. The volume is given in terms of round timber and includes stump. It is calculated on full basal area basis from overbark diameters, but standard stem timber excludes the volume of bark while standard small wood includes it.
  2. Commercial Volume Table: Volume tables in which contents of round timber are given as volume measured down to a thin end diameter to which conversion is done, the stump volume being omitted.
    A market requirements decide the minimum limit of exploitation. Scope of applicability is limited.
  3. Sawn Outturn Tables: Volume tables in which contents of sawn timber are given as volume measured down to a thin end diameter to which conversion is done, the stump volume being omitted.
  4. Assortment Tables: Volume tables which give volume in round down to various stated thin diameters. For example, it will be possible to find out volume of a tree of given linear dimensions when the conversion was done up to 25 cm, 20cm or 15 cm diameter limit.
  5. Sawn Outturn Assortment Table: Similar to assortment tables except they give sawn outturn in the number of standardized pieces instead of volume in round
 

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