The yield table system of ForestElementsR allows easy use
of yield tables that are available as an fe_yield_table object.
Here, we list all yield tables that come with the current version of the
package. For test purposes and as an example, the Scots Pine table by
Wiedemann (1943) is provided as a raw data frame (prefix "ytable_") and an
fe_yield_table object (prefix "fe_ytable_"). The raw data frame can be
transformed into a fe_yield_table object with the function
fe_yield_table (see the example there).
When we refer to Schober's yield table collection below, we mean
ertragstafeln_schober_1975;textualForestElementsR. Many of
the yield tables listed were implemented in the version published in what we
refer to as the Hilfstafeln edited by the Bavarian Forest Administration.
Hereby, we mean, more precisely,
hilfstafeln_bavaria_1990;textualForestElementsR, and
hilfstafeln_bavaria_2018;textualForestElementsR. The yield
table collection in both editions is almost identical, and represented
in ForestElementsR (including error corrections beyond the 2018
edition). Only the yield table by Kenk and Hradetzky for Douglas fir that is
new in the 2018 hasn't been imported here, yet.
The following yield tables are currently implemented (alphabetically ordered by author names):
Assmann-Franz 1963, Norway Spruce, Mean Yield Level: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. The total volume production (tvp), mean annual increment (mai), and the periodic annual increment were given as reduced values (under bark, harvest losses substracted) only. Thus, they were converted into standing m³ over bark by dividing them by 0.81 (standard factor for Norway spruce in Bavaria). The yield table allows site indexing based on the dominant height h100, and the quadratic mean height hq, whereby the former is the way Ernst Assmann and Friedrich Franz had in mind. The site index of this table is, unusual for German yield tables, given as a stand's expected dominant height at an age of 100 years. Unlike in most yield table, the number of removal trees (n_rmv_ha), the volume of the removal stand (v_rmv_ha), and the periodic annual increment (pai_m3_ha_yr, red_m3_ha_yr) relate to the subsequent, not the previous time span. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume.
Bauer, 1955, Red Oak: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. In the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights were taken from the version published in Schober's (1975) yield table collection for the whole site indexes (I.0, II.0, etc.). The values for the site indexes I.5 and II.5 were generated by linear inter- and extrapolation. The total volume production was not contained in the Bavarian edition of the table; so, it was added from the version published in Schober's (1975) collection. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 21 % which takes into account both, harvest losses (mainly stump) and bark volume.
Blume, 1949, Poplar: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. Originally, this table was designed for site indexing by quadratic mean diameter (d_q_cm), not by height. Therefore, this diameter was given in the table as lower threshold, here listed as "d_q_cm_si_plus_025". As site indexing by height is always preferable, options for site indexing by both, diameter and height, were included in the fe_yield_table representation of this table. The actual quadratic mean diameter (d_q_cm) which is used for site indexing if the user decides so was calculated from dividing the given basal area by the stem number, multiplying it with 4/pi, and taking the square root of the result. The total volume production (tvp) was not contained in the Bavarian edition of the table. Therefore, it was re-calculated by multiplying the table's mean annual increment (mai) with the stand age. Despite the lower diameter threshold for site indexing, the table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume. Overall, this table seems not really well constructed, the time-curves of its variables are often not intuitively plausible. Some inconsistencies (e.g. decreasing tvp resulting from a to low mean annual increment value) were corrected.
Gehrhardt, 1908, European Beech, Moderate Thinning:Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights, as required for automated use were generated by inter- and extrapolation. The total volume production (tvp) was not contained in the Bavarian edition of the table. Therefore, it was re-calculated by multiplying the table's mean annual increment (mai) with the stand age. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 15.4 % which takes into account both, harvest losses (mainly stump) and bark volume. The quadratic mean diameter (d_q_cm) for site index 2.0 was obviously wrong in the source data. It was corrected by interpolation.
Gehrhardt 1921, Norway Spruce, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights, as required for automated use were generated by inter- and extrapolation. The total volume production (tvp) was not contained in the Bavarian edition of the table. Therefore, it was re-calculated by multiplying the table's mean annual increment (mai) with the stand age. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume.
Gehrhardt, 1921, Scots Pine, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights, as required for automated use were generated by inter- and extrapolation. The total volume production (tvp) was not contained in the Bavarian edition of the table. Therefore, it was re-calculated by multiplying the table's mean annual increment (mai) with the stand age. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 21 % which takes into account both, harvest losses (mainly stump) and bark volume.
Guttenberg, 1915, Norway Spruce, High Mountains: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights, as required for automated use were generated by inter- and extrapolation. The total volume production (tvp) was not contained in the Bavarian edition of the table. Therefore, it was re-calculated by multiplying the table's mean annual increment (mai) with the stand age. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume. The interpolated site indexes contained many mistakes (highlighted in the source data), mostly in the mai which could, however, be easily corrected by interpolation between the adjacent site index tables.
Hausser 1956, Silver Fir, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. In the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights were taken from the version published in Schober's (1975) yield table collection for the whole site indexes (I.0, II.0, etc.). The values for the site indexes I.5, II.5, etc. were generated by linear inter- and extrapolation. The total volume production was not contained in the Bavarian edition of the table; so, it was added from the version published in Schober's (1975) collection. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume.
Juettner 1955, Oak, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. In the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights were taken from the version published in Schober's (1975) yield table collection for the whole site indexes (I.0, II.0, etc.). The values for the site indexes I.5, II.5, etc. were generated by linear inter- and extrapolation. The total volume production was not contained in the Bavarian edition of the table; so, it was added from the version published in Schober's (1975) collection.
Mitscherlich, 1945, Black Alder: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights, as required for automated use were generated by inter- and extrapolation. The total volume production (tvp) was not contained in the Bavarian edition of the table. Therefore, it was re-calculated by multiplying the table's mean annual increment (mai) with the stand age. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume.
Schober 1946, European Larch, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights were taken from the version published in Schober's (1975) yield table collection for the whole site indexes (I.0, II.0, etc.). The values for the site indexes I.5, II.5, etc. were generated by linear inter- and extrapolation. The total volume production was not contained in the Bavarian edition of the table; so, it was added from the version published in Schober's (1975) collection. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 28 % which takes into account both, harvest losses (mainly stump) and bark volume. There were some mistakes in the mean diameters and basal areas of the interpolated site index tables I.5 (most) and II.5 (less). These have been corrected by interpolating between the original values of the integer site index tables (I.0, II.0, III.0).
Schober, 1953, Japanese Larch, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. In the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights were taken from the version published in Schober's (1975) yield table collection for the whole site indexes (I.0, II.0, etc.). The values for the site index I.5 were generated by linear inter- and extrapolation. The total volume production was not contained in the Bavarian edition of the table; so, it was added from the version published in Schober's (1975) collection. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 28 % which takes into account both, harvest losses (mainly stump) and bark volume.
Schober 1956, Douglas Fir, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights, as required for automated use were generated by inter- and extrapolation. The total volume production (tvp) was not contained in the Bavarian edition of the table. Therefore, it was re-calculated by multiplying the table's mean annual increment (mai) with the stand age. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 21 % which takes into account both, harvest losses (mainly stump) and bark volume.
Schwappach, 1903/29, Birch: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. In the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights were taken from the version published in Schober's (1975) yield table collection for the whole site indexes (I.0, II.0, etc.). The values for the site indexes I.5 and II.5 were generated by linear inter- and extrapolation. The total volume production was not contained in the Bavarian edition of the table; so, it was added from the version published in Schober's (1975) collection. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume. An obvious interpoliation error was corrected (site index 1.5, basal area at age = 40 years).
Vanselow, 1951, Norway Spruce, Southern Bavaria: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights, as required for automated use were generated by inter- and extrapolation. The total volume production (tvp) was not contained in the Bavarian edition of the table. Therefore, it was re-calculated by multiplying the table's mean annual increment (mai) with the stand age. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume. Two values, basal area at age 20 and standing volume at age 40 for site index I.5 were obviously wrong, probably due to interpolation errors. Both values were replaced by those obtained from correct interpolation between site indexes I and II.
Wiedemann 1931, European Beech, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights, as required for automated use were generated by inter- and extrapolation. The total volume production (tvp) was not contained in the Bavarian edition of the table. Therefore, it was re-calculated by multiplying the table's mean annual increment (mai) with the stand age. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 15.4 % which takes into account both, harvest losses (mainly stump) and bark volume. Site index I.5, age 130: Mistake in n_ha, value 465 was wrong. Linearly interpolated from the neighboring values to 238.5.
Wiedemann 1936/42, Norway Spruce, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights were taken from the version published in Schober's (1975) yield table collection for the whole site indexes (I.0, II.0, etc.). The values for the site indexes I.5, II.5, etc. were generated by linear inter- and extrapolation. The total volume production was not contained in the Bavarian edition of the table; so, it was added from the version published in Schober's (1975) collection. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume. Several mistakes were found in the source files, especially consistently wrong stem numbers and mean diameters in site indexes 4 and 5.
Wiedemann 1943, Scots Pine, Moderate Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. in the source files, the quadratic mean height of the site index classes was only available as lower threshold (i.e 1/4 site index lower). So the original heights were taken from the version published in Schober's (1975) yield table collection for the whole site indexes (I.0, II.0, etc.). The values for the site indexes I.5, II.5, etc. were generated by linear inter- and extrapolation. The total volume production was not contained in the Bavarian edition of the table; so, it was added from the version published in Schober's (1975) collection. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume means is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 21 % which takes into account both, harvest losses (mainly stump) and bark volume. The Bavarian original values had a mistake in N/ha, site index I.0, age 95: 343 (wrong) instead of 373 (right), correct value was taken from the version in Schober's (1975) yield table collection.
Wimmenauer-Schwappach, 1919/29, Ash, Weak Thinning: Imported from the "Hilfstafeln" edited by the Bavarian Forest Administration. The table follows the standard structure of all tables that are part of the Bavarian "Hilfstafeln": Stem number, mean diameter, standing volume, and basal area describe the remaining stand. Wood volume is defined as standing coarse wood over bark. Variables whose names begin with "red_" relate to harvested volume under bark; i.e. reduced by 19 % which takes into account both, harvest losses (mainly stump) and bark volume.
fe_ytable_spruce_assmann_franz_mean_yield_level_1963fe_ytable_poplar_blume_1949
fe_ytable_redoak_bauer_1955
fe_ytable_beech_gehrhardt_moderate_1908
fe_ytable_spruce_gehrhardt_moderate_1921
fe_ytable_pine_gehrhardt_moderate_1921
fe_ytable_spruce_guttenberg_1915
fe_ytable_silver_fir_hausser_moderate_1956
fe_ytable_oak_juettner_moderate_1955
fe_ytable_blackalder_mitscherlich_heavy_1945
fe_ytable_larch_schober_moderate_1946
fe_ytable_japanlarch_schober_moderate_1953
fe_ytable_douglas_schober_moderate_1956
fe_ytable_birch_schwappach_1903_29
fe_ytable_beech_wiedemann_moderate_1931
fe_ytable_spruce_wiedemann_moderate_1936_42
fe_ytable_pine_wiedemann_moderate_1943
ytable_pine_wiedemann_moderate_1943_raw
fe_ytable_ash_wimmenauer_1919_29
fe_ytable_spruce_vanselow_1951
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.
An object of class tbl_df (inherits from tbl, data.frame) with 237 rows and 16 columns.
An object of class fe_yield_table of length 7.
An object of class fe_yield_table of length 7.