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Forest Vegetation Simulator

Forest Vegetation Simulator (FVS) and Suppose File Formats

Suppose and FVS use three different types of files. The first is a FVS formatted file and the second and third are specific to Suppose. Each has a different file extension.

  1. FVS Tree Data File (<filename>.fvs)
  2. Suppose Stand List File (<filename>.slf)
  3. Suppose Locations File (<filename>.loc)

Most Forest Service Regions have data translators that format regional-specific data into Suppose and FVS formatted files. Examples of these regional-specific translators are R1-EDIT, RMSTAND, R5TRANS, R6TRANS, SUPERSTAND, R9TRANS, and Pre-Suppose.

FVS Tree Data Input Format

Each stand or inventory plot has its own FVS tree data input file. Each tree (or group of similar trees on a plot) has an entry in the file. There are no distinguishing record type names in the FVS tree data input files, but the data must follow a specific format. Tree data items must be in defined columns as described below.

Columns FORTRAN Data Type FORTRAN Format Description
1-4 Integer I4 Plot Identification (i.e., plot numbers)
5-7 Integer I3 Tree identification (when combined with the Plot ID, the value should be unique for each tree record)
8-13 Real F6.0 Tree count (number of sample trees this record represents; can be more than one)
14 Integer I1 Tree history code
15-17 Character A3 Species code (can also enter the 3-digit Eastwide Database Species Code)
18-21 Real F4.1 Diameter at breast height (nearest tenth of an inch, outside bark)
22-24 Real F3.1 Diameter increment (nearest tenth of an inch, inside bark)
25-27 Real F3.0 Live height (feet)
28-30 Real F3.0 Height to top kill (feet)
31-34 Real F4.1 Height increment (nearest tenth of a foot)
35 Integer I1 Crown ratio code
36-39 Integer I2, I2 First pair of tree damage and severity codes
40-43 Integer I2, I2 Second pair of tree damage and severity codes
44-47 Integer I2, I2 Third pair of tree damage and severity codes
48 Integer I1 Tree value class code
49 Integer I1 Cut or leave prescription code
50-51 Integer I2 Plot slope percent code
52-54 Integer I3 Plot aspect code
55-57 Integer I3 Plot habitat type code
58 Integer I1 Plot topographic position code
59 Integer I1 Plot site preparation code
60-62 Integer I3 Tree Age

The FVS geographic variants vary in whether they use all of the preceding information or use the same codes. Refer to the individual variant documentation for specific descriptions of the information the variant uses.

The FVS Tree Data can be viewed, edited, or both within Suppose using the "Options" menu item, "Edit FVS Tree Data". These files can also be viewed and edited using your favorite text editor.

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Stand List File Format

The "Stand List File" (.slf file extension; also called the SLF file) contains the plot header information for a particular stand. All stands that comprise a geographic location listed in the Suppose.loc file are contained in separate Stand List Files.

The records in this file are coded free form. There are four Record Types: A, B, C, and D. Record Types A and B are required entries. Record Types C and D are optional. A Stand List File can be edited within Suppose by selecting the "Options" menu item, "Edit Stand List File". A Stand List File can also be edited outside of Suppose by using your favorite text editor.

Record Type A

Field 1: Record Type, always code an 'A'.
Field 2: Stand Identification code. Limited to 26 characters.
Field 3: FVS-ready tree data file name.
Field 4: Sample point site data flag. "WithPointData" indicates that the sample points within sample plots contain independent site data in the tree data. "NoPointData" indicates otherwise. Sample point site data are point measures of slope, aspect, habitat type, topographic position, and site preparation.
Field 5: FVS Variants to which the plot and tree data apply. This field is a list of 2-character variant identifiers (always in lower case). The list is ended with an @ symbol.

Record Type B

Field 1: Record Type, always code a B.
Field 2: Stand Identification code. Limited to 26 characters and must be identical to that used in record type A.
Field 3: Inventory year. For permanent plots, designate last growing season.
Field 4: Latitude in degrees.
Field 5: Longitude in degrees.
Field 6: Location code. Usually the USFS Region and Forest Code, 3-digits.
Field 7: Habitat type or Plant Association.
Field 8: Stand Year of Origin.
Field 9: Aspect in degrees.
Field 10: Slope percent.
Field 11: Elevation in 100's of feet.
Field 12: Positive value = Basal area factor / Negative value = Inverse of large-tree fixed area plot in acres.
Field 13: Inverse of small-tree fixed area plot in acres.
Field 14: Breakpoint DBH in inches between large-tree and small-tree sample design.
Field 15: Number of plots (not points) represented associated tree file.
Field 16: Number of non-stockable plots.
Field 17: Stand sampling weight (or size) used to compute weighted average yield tables and other weighted averages among some set of stands.
Field 18: Stockable percent.
Field 19: Diameter growth translation code as defined for FVS.
Field 20: Diameter growth measurement period.
Field 21: Height growth translation code as defined for FVS.
Field 22: Height growth measurement period.
Field 23: Mortality measurement period.
Field 24: Maximum basal area.
Field 25: Maximum stand density index.
Field 26: Site Index Species.
Field 27: Site Index.
Field 28: Model Type.
Field 29: Physiographic Region Code.

Record Type C

(This record is optional and more than one per stand may be used)
Field 1: Record type, code a C
Field 2: Stand Identification code. Must be identical to that used in record type A
Field 3: Group code 1 (must not contain blanks)
Field 4: Group code 2 (must not contain blanks)
Filed n+2: Group code n (must not contain blanks)
Field n+3: @ symbol specifying the end of the group codes for this record.

Record Type D

(This record is optional and more than one per stand may be used)
Field 1: Record type, code a D
Field 2: Stand Identification code. Must be identical to that used in record type A
Field 3: Addfile name 1
Field 4: Addfile name 2
Field n+2: Addfile name n
Field n+3: @ symbol specifying the end of the addfile names for this record.

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Suppose Locations File Format

The name of the locations file is usually "suppose.loc". It contains two kinds of records. Record type A is required, record type B is optional. There is one type A record for each location. Each location refers to a list of stands and/or inventory plots. Each stand is further defined via entries in a different file, the stand list file (.slf extension). The name of the stand list file is one of the entries on the type A records in the suppose.loc file.

The second type of record in the suppose.loc file, called type B, is used to specify group codes and addfiles applicable to all the stands at all the locations. Addfiles identified on type B records are automatically included in the simulation file for each stand that is identified as being a member of the group. Group membership is defined on type C records of the stand list file.

The locations file is coded free form. It can be edited using the Edit Locations File window accessible via the options menu on the main Suppose selections window. It can also be edited outside of Suppose with a text editor.

Record Type A

Field 1: Record type, always code an A
Field 2: Location name, entered as a quoted string if it contains blanks. This string will be used in the Select Simulation Stands window to provide a list of locations. If an @ sign is entered, the SLF filename will be used as the location name.
Field 3: SLF access method code where an @ symbol signifies the default (Suppose-ready data)
Field 4: SLF file name. Code an @ symbol if the access method does not require this name.
Field 5: Mapfile type identifier. Code an @ symbol because this file is not used in Suppose Version 1 or greater.
Field 6: Name of the map file. Code an @ symbol because this file is not used in Suppose Version 1

Record Type B

(This record is optional)
Field 1: Record type, always code a B
Field 2: Grouping code: may not contain blanks
Field 3: Name of the first addfile. This file will be inserted into the simulation file as one or more components.
Field 4: Name of the second addfile.
Field n+2: Name of the nth addfile
Field n+3: @ sign signaling the end of the addfiles.

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Last modified: Wednesday, 26-Jun-2013 10:27:57 CDT