ControlTable Treatment Model

Overview of TreatmentModel control table parameters.
For a more detailed description of the usage, see the help documention chapters on simulation of treatments, for example:

• Regeneration: Regeneration help documention
• Cleaning: Cleaning (precommercial thinning) help documention
• Thinning: Thinning help documention
• Final felling: Final Felling help documention

In the treatment model control table you can configure how individual forest management activities are simulated.

Regeneration - model

Allows you to control how forest regenerations are simulated, regarding planting, natural regeneration using seed trees, and sowing.

Regeneration Model Type

• Simulation: simulate regeneration from a Weibull distribution.
• Database: simulate regeneration by imputation of plot data from a database (supplied).

Regeneration - settings

Deterministic Application

(only if Simulation is selected) True applies deterministic regeneration model components, False do not (then stochastic).

Mean Sapling Height When Activated

(only if Simulation is selected)

Defines the arithmetic mean height in meters at stand-level[plot-level?] when trees are initiated, for Natural regeneration, Sowing, Spruce plantation, Pine plantation, and Contorta plantation, respectively. Development before this height is obtained by linear interpolation.

Regeneration Year

Defines the number of years from time of final felling to time of regeneration, applied in simulations of Plantation and Sowing.

Regeneration Settings

Defines the number of seedlings per hectare applied in Plantation (or in Sowing, or in Natural regeneration using seed trees, respectively) following Soil scarification (or Controlled burning, or None, respectively), regarding the tree species and site index. This seedling consumption table will, obviously, lead to certain regeneration costs.

Soil Preparation Year

Defines the number of years from time of final felling to time of soil preparation, applied in simulations of Soil scarification and Controlled burning. Obviously, this number can not exceed settings in Regeneration Year.

Cleaning

Allows you to control how cleanings, a.k.a. pre-commercial thinnings, are simulated.

Cleaning Model

Heureka cleaning defines one model of tree removal, actually cutting of saplings, in the cleaning simulations.

Hugin cleaning defines another model of tree removal, currently corresponding to the above, in the cleaning simulations.

Deterministic Application

True applies deterministic cleaning model components, False do not (then stochastic).

Mean Height Cleaning

Min defines the minimum arithmetic mean height in meters at stand-level when cleaning is simulated.

Max defines the maximum arithmetic mean height in meters at stand-level when cleaning is simulated.

Min Stems Cleaned

Defines the minimum number of stems per hectare to be cut in cleanings. No cleaning will be simulated if stem density is so low that less stems are able to cut, regarding all current tree species.

Settings for Deciduous Trees

Alfa and Beta are coefficients in a function calculating the priority factor of deciduous tree species. Deciduous trees, i.e. all broadleaves, will then be retained in cleanings prior to coniferuous trees.

Settings for Pine

Alfa and Beta are coefficients in function calculating the priority factor of pine trees. Pines, i.e. Pinus ssp., will then be retained in cleanings prior to deciduous and other coniferuous trees.

Settings for Spruce

Alfa and Beta are coefficients in function calculating the priority factor of spruce trees. Spruces, i.e. Picea ssp. and Abies ssp., will then be retained in cleanings prior to deciduous and other coniferuous trees.

Thinning or Selection Felling

Settings in common for thinning and selection felling

Thinning Configuration

Opens a dialog where you can select Thinning Algoritm and how different species should be prioritized. See Help doc on thinning settings.

The thinning algorithm that can be selected are:

HuginOld Algorithm developed for the Hugin system. It uses three species groups, and groups trees into four diameter classes for each group. See Thinning

Hugin Derived from HuginOld but allows you to specify more species groups, and explicit species distribution targets. The algorithm operates on a species group level in the same way as HuginOld. See Thinning

LOEriksson defines another model of tree selection in the thinning simulations. You enter species groups in the same ways as with Hugin, but the thinning form (above/below) is entered using a relative diameter target value.

The dialog contains parameters for how thinning should be distributed over trees and species, depending on the thinning algorithm chosen.

Relative Diameter

(only if LOEriksson is selected)

First defines the relationship between the mean diameters of trees cut and trees retained in first thinning of a stand, expressed in percentage.

Second defines the relationship between the mean diameters of trees cut and trees retained in second and following thinnings of a stand, expressed in percentage.

Thinning Algorithm Parameters

See Thinning Algorithm Parameters

Vary Thinning Grade

True: thinning intensity is distributed over PredictionUnits (plots) proportionally to basal area. False: Same thinning intensity on all plots in the treatment unit.

Min Diameter Cut

Defines the minimum diameter, in centimeters, of trees to be cut when thinning or selection felling.

Min Prop. Thinnable Plots

Min proportion of plots (impediment plots ignored) that should be thinned according to thinning guide in order for thinning to be applied. Currently only available when Thinning Guide = StemDensity.

Min Thinning Grade

Defines the minimum thinning grade required in order to apply a thinning, in percentage of basal area, stem density or volume (depending on thinning guide), including any cutting of strip roads. Is thinning grade accoring to guide is lesser, thinning is cancelled.

Max Thinning Grade

Defines the maximum thinning grade, in percentage of basal area, stem density or volume (depending on thinning guide), including any cutting of strip roads. If thinning guide suggest a larger thinning grade, it is set to Max Thinning Grade.

Thinning System

These parameters are only used in cost functions and should not be confused with settings for how a thinning should be simulated.

• NotSpecified: defines that non specified thinning types should be simulated.
• StripRoad: defines that thinnings with strip roads should be simulated.
• StripRoadMidFieldMachine: defines that thinnings with harvester should be simulated.
• StripRoadMidFieldChainsaw: defines that thinnings with harvester and manual labour (with chainsaw) should be simulated.

Harvest Striproads

True simulates the cutting of strip roads if a stand is thinned for the first time, False do not.

Effective Striproad Width

Defines the effective width of strip roads in meters. Effective means that the harvesting machines can thread (slingra sig fram). A "threading factor" (slingerfaktor) of 75 % gives an effective strip road width of 3 m with an actual strip road width of 4 m.

Distance Between Striproads

Defines the distance in meters between the centre of adjacent stip roads, used in simulation of the first thinning in a stand.

Thinning

Allows you to control how thinnings are simulated. See Thinning for a complete description.

UMin

(only if LOEriksson is selected as thinning algorithm in Thinning Configuration Dialog)

Defines the minimum proportion, regarding basal area, of a single tree of all trees cut at the plot-level, expressed in percentage and value range (0, 20).

UMax

(only if LOEriksson is selected as thinning algorithm in Thinning Configuration Dialog)

Defines the maximum proportion, regarding basal area, of a single tree of all trees cut at the plot-level, expressed in percentage and value range (80, 100).

Thinning Guide

A thinning guide is used to determine whether thinning should or could be done, and the thinning intensity.

Hugin, Skogsstyrelsen, Ingvar, Logarithmic and Polynomial are defined for basal area.

StemDensity is defined for number of trees.

Thinning Guide Settings

All guides but StemDensity and Ingvar

Opens dialog with coefficients for thinning guide (such as site index and dominant height, respectively) used in calculations of the tree species' basal area, before and after thinning.

Thinning Guide Stem Dens. Beta: Setting for thinning guide "StemDensity", parameter β = Domainant height at which first thinning should be done.

Thinning Guide Stem Dens. Delta:Setting for thinning guide "StemDensity". This parameter controls slope of function.

Ingvar version: Ingvar thinning guide (by Skogforsk) has different levels.

Max Relative Age

Time for last thinning in terms of maximum relative age. If relative age is larger, then no more thinning will be simulated. Relative age is an approximation for how close a stand is to culmination of mean annual growth (MAI). It is computed as mean age divided by 1.1*LSÅ, where LSÅ = minimum eligible age for final felling according to Swedish Forestry Act.

Min Height Thinning

Min dominant height required for thinning.

Max Height Any Thinning

Max dominant height (m) when last thinning can be applied. Currently only available when Thinning Guide = StemDensity.

Max Height First Thinning

Max dominant height (m) when first thinning can be applied. If dominannt height is larger and stand has never been thinned, then it is considered too late to do first thinning, due to risk of felling damages on remaining trees.

Thinning Guide Reduction Factors

Thinning guide reduction factors for upper and lower curve. Applies to basal area thinning guides. Example: 0.95 for upper curve means that upper curve is lowered by 5 percent.

Previously Thinned Threshold

Threshold for when stands of a given SIS is considered previously thinned if thinning history is not available. If stems/ha is lower than given value, stand is assumed to have been thinned.

Pine Threshold

Maximum stem density (stems/ha) in pine stands to consider them as previously thinned if thinning history is missing.

Spruce Threshold

Maximum stem density (stems/ha) in spruce stands to consider them as previously thinned if thinning history is missing.

Other Threshold

Maximum stem density (stems/ha) in deciduous stands to consider them as previously thinned if thinning history is missing.

Understorey Max Diameter

Upper diameter limit for understorey trees in thinnings (cm). Trees with dbh lesser than this value will be considered understorey trees (in mature stands, not in plantations). Note: Setting this to 0 means that no trees will be considered understorey trees.

Default: 8 cm

Understorey Cleaning Stems Threshold

Minimum understorey stem density required for understory cleaning to be performed (stems/ha). If the number of understorey stems is less than this parameter, no understorey cleaning will be performed, but the harvester cost may increase due to the hindrance of understorey. For example, with 4000 undestorey trees, the harvester productivity will decrease with 3 percent.

Default: 800 st/ha

Min Understorey Stems Retained

Minimum number of understorey trees left when understorey cleaning is done.

Default: 200 st/ha

Understorey Proportion Removal

Proportion of understorey stems to remove when and if understorey cleaning is performed (%). The program may adjust so that parameter 'Min Understorey Stems Retained' is not violated.

Default: 90%

Selection felling

(only if Hugin is selected as thinning model) Allows you to control how selection fellings (usually applied in "continuous forestry") are simulated.

SelectionControlParameter

Equivalent to Thinning Algorithm Parameters but other settings for selection fellings.

Young Stand Thinning

Criteria to determine whether a stand should be considered a young stand. Biofuel thinning is only allowed in stands classified as young. Also, to determine whether a stand is a young stand thinned for the first time (swe: förstagallring), this information is used.

Max Relative Age

Max relative age for a stand to be considered young. Relative age is a ratio of stand age and "mature" age, see [1]].

Max Age

Max age for a stand to be considered a young stand

Min Height

Minimum height for a stand to be considered young, but old enough for thinning

Max Height

Maximum height for a stand to be considered young

Thinning Type

Ordinary

Biofuel

Understorey Density Trigger Biofuel Thinning

(From version 2.11) Understorey stem density when thinning is automatically switched to biofuel thinning (stems/ha). In this case no understorey cleaning will be done. Leave blank or set to a negative number to inactivate.

Final Felling

Allows you to control how final fellings (sometimes referred to as "clear cuttings") are simulated.
See also: Help chapter on final felling

Min Diameter in Final Felling

Defines the minimum diameter, in centimeters, to be cut in the simulations.

Seed Tree Retention

(only if SeedTree or Shelterwood is selected) Same as ThinningControlParameter

Shelterwood Retention

(only if Seed Tree or Shelterwood is selected) Note: Do not confuse with Tree Retention in control table Nature Conservation

• RetainedBasalAreaLowSI: The basal area, in m²/ha, of seed trees and shelterwood to be retained in stands with site index less than 20 m. *RetainedBasalAreaHighSI: The basal area, in m²/ha, of seed trees and shelterwood to be retained in stands with site index greater than 20 m.
• RemovalTime: The number of years from final felling to when retained trees are cut.
• RetainDominantSpecies: If True, retain trees of the dominant tree species, False do not.
• MinimumRetainedBasalArea: The minimum basal area, in m²/ha at the stand-level, of seed trees and shelterwood to be retained.
• RetainedSpecies: (only if RetainDominantSpecies is False) The tree species to be retained as seed trees and shelterwood.

Remove Existing Overstorey

Regulates how shelterwood, seed trees or retention trees (trees left for the next rotation) will be handled. With the latest template for stand register, you will also be able to specify suggestions for treatments and control how they are used in each stand. Existing trees retained for nature conservation can also be treated separately in the new version.

Use SI Management

Set Use SI Management to True if you have typed values in the Site Index Management column in the stand register (version 3), and you want to use them to govern the minimum age of final felling. If you use the Forest Management Planning Package (FMPP) and have a stand register linked to it with values for the Site Index Management column, the latter will be given precedence. If SI Management is set to False, or SI Management is missing, SIS is used (Site quality index according to site factors).

Fertilization

Allows you to control how fertilizations are simulated.

FertilizerAmount

Defines the amount of fertilizer in kilogram per hectare used in the simulations.

FertilizerSubstance

AN defines that ammonium nitrate is the active substance in fertilizations.

UREA defines that urea, i.e. ammoniac[?], is the active substance in fertilizations.

MaxAnnualGrowth

Defines the maximum annual growth, in m³sk/ha, if fertilization of the stand is to be simulated.

MeanHeightLimitFertilization

Defines the minimum average height (basal area weighted) in meters if fertilization of the stand is to be simulated.

MinConiferProportion

Defines the minimum proportion of conifers, in percentage of basal area, if fertilization of the stand is to be simulated.

SiteIndex

Min defines the minimum site index value in meters if fertilization of the stand is to be simulated.

Max defines the maximum site index value in meters if fertilization of the stand is to be simulated.

Intensive Fertilization

Allows you to control how intensive fertilization is simulated.

Note that intensive fertilization can only be simulated if the soil moisture is mesic or mesic-moist, in the southern part (latitude <58° N) and the central part (58-61° N) of Sweden also moist soils are possible to intensively fertilize. Moreover, the site index (H100, m) must in the northern part of Sweden (>61° N) be below G26, in the central part below G30, and in the southern part below G34, to allow for intensive fertilization.

HeightIntensiveFertilization

Min defines the minimum average height in meters if fertilization is to be initiated in the young stand.

Max defines the maximum average height in meters if fertilization is to be initiated in the young stand.

MinSpruceProportionIntensiveFertilization

Defines the minimum proportion of spruce, in percentage of basal area (or of stems per hectare), if fertilization is to be initiated in the young stand.

MinStemsIntensiveFertilization

Defines the minimum number of stems per hectare if fertilization is to be initiated in the young stand.

Biofuel

Allows you to control how forest fuel extractions are simulated.

Restrictions

• MinSpruce: defines the minimum proportion of spruce, in percentage of basal area, if extraction is to be simulated.
• MaxDiamStump: defines the maximum diameter, in centimeters, of the stump if extraction is to be simulated.
• MinDiamStump: defines the minimum diameter, in centimeters, of the stump if extraction is to be simulated.

Stump Extraction

Selection of species for which stumps and roots can be extracted. For each species to extract, set value to True.

Utilization

• Top: defines the proportion, in percentage, of the top (incl. stem, branches, and needles) that is utilized in extraction.
• BranchesNotTop: defines the proportion, in percentage, of the branches below the top that is utilized in extraction.
• BranchesTop: defines the proportion, in percentage, of the branches of the top that is utilized in extraction.
• DeadBranchesNotTop: defines the proportion, in percentage, of the dead branches below the top that is utilized in extraction.
• DeadBranchesTop: defines the proportion, in percentage, of the dead branches of the top that is utilized in extraction.
• NeedlesTop: defines the proportion, in percentage, of the needles of the top that is utilized in extraction.
• NeedlesNotTop: defines the proportion, in percentage, of the needles below the top that is utilized in extraction.
• Stump: defines the proportion, in percentage, of the stump that is utilized in extraction.

Nature Conservation Activities (Tree Retention)

(moved here from Nature Conservation control table in version 2.9)
Allows you to control if trees should be retained, as a part of the simulation of the biological considerations to be taken.

Tree Retention Settings

(only if Retain Trees = True) Allows you to control how trees are to be retained.

Retain Trees?

True: Selected trees (according to settings below) should be left after final felling or after selecion felling, and left until the next final felling or selection felling at which a new decision taken what trees to retain.

False: No nature conservation trees should be retained.

Retained Trees/ha

Mumber of trees to retain (per hectare).

Retention Priority

Priority settings for which trees to retain as nature conservation trees, regarding species, age and size.

Retention Time

Defines for how long trees are retained (in years). After this time the retained trees will be transferred to downed, coarse woody debris (the "dead wood").

Retention of High Stumps

Leave High Stumps?

If set to True, high stumps will be "created" at final felling. Unlike retention trees, high stumps immediately become part of the dead wood pool of standing dead trees, with a volume reductions for the part of the tree that was harvested.

High Stumps/ha

Mumber of high stumps to create (per hectare).

Height of High Stumps

This is set in the Pricelist Manager (which control the bucking of trees when harvesting).

High Stump Priority

Priority settings for which trees to leave high stumps for, regarding species, age and size.

Leave stems in forest after treatment

Allows you to control the proportion of stems to be left in the forest as deadwood, after a thinning or selection felling.