USER'S GUIDI TO A MULTIPURPOSE FOREST PROJECTION SYSTEM FOR SOUTHERN FORESTS Bulletin 604 January 1990 Alabama Agricultural Experiment Station Lowell T. Frobish, Director Auburn University Auburn University, Alabama CONTENTS Page INTRODUCTION ............................................ MULTIPURPOSE FOREST PROJECTION SYSTEM FOR GEORGIA (GATWIGS) ................................. Input.................. .............. ............... EXECUTING GATWIGS ............. .......................... SUM M ARY ..................... ............ ............ LITERATURE CITED ......................................... APPENDIX 1. FOREST TYPE DEFINITIONS ..................... APPENDIX 2. SPECIES CODE-COMMERCIAL TREES ............ 3 5 5 6 8 9 11 . 13 Yellow Pines............................. ............. 13 Other Softwoods................................... 13 Soft Hardwoods...................................13 Hard Hardwoods..................................14 Miscellaneous Species................................ 15 FIRST PRINTING 3M, JANUARY, 1990 Information contained herein is available to all without regard to race, color, sex, or national origin. USER'S GUIDE to a Multipurpose Forest Projection System for Southern Forests1 ROGER K. BOLTON and RALPH S. MELDAHL2 A INTRODUCTION PPROXIMATELY 40 percent of the timberland in the United States is located in the South. This publication is a brief introduction and user's guide for a projection system based on data from the State of Georgia 3 . This system allows various management options to be explored on forestland, not only in Georgia but in similar adjoining areas in the South. Georgia is the largest state east of the Mississippi River, with a total land area of 37.3 million acres. Of this total land area, 64 percent is classified as commercial forestland (7). These forests support a large forest industry and provide wildlife habitat, watershed protection, and a range of outdoor recreational opportunities. Within this resource, a prodigious amount of diversity occurs. For example, Georgia is often divided into five physiographic regions. The five physiographic regions, shown in figure 1, are the Lower Coastal Plain, the Upper Coastal Plain, the Piedmont, the Valley and Ridge, and the Blue Ridge Mountains (8). These regions are occupied by six major forest types (loblolly pine, shortleaf pine, slash pine, oak-pine, oak- hickory, oak-gum-cypress), a copious mixture of species, and a mixture of stand conditions. Due to the complex structure of natural stands and the myriad conditions found within Georgia, a distance-independent, individual tree model was selected for the modeling methodology (5). In this 'Project jointly funded by the Alabama Agricultural Experiment Station, Forest Resources System Institute (FORS), and Georgia Forestry Commission. 2 Research Associate and Assistant Professor of Forestry. 'Details about the projection system are reported in Alabama Agricultural Experiment Station Bulletin 603, "Design and Development of a Multipurpose Forest Projection System for Southern Forests." ALABAMA AGRICULTURAL EXPERIMENT STATION n nr A~A A A~~IT\I Lower Coastal Plain Piedmont Blue Ridge Upper Coastal Plain FIG. 1. Physiographic regions of Georgia. type of system, the growth and mortality of individual trees in a stand are projected into the future by using a set of equations. The data base to derive these equations consisted of the 1980 Forest Service FIA data of Georgia, from the Southeastern Forest Experiment Station. Models were developed from these data to predict live crown ratio, annual diameter increment, mortality, and bole length. Many of the approaches used in modeling were new and/or differed from previous projection systems. For example, as a means USER'S GUIDE TO FOREST PROJECTION SYSTEM of organizing the diversity of forest conditions, heavy use was made of cluster analysis. A more in-depth presentation of the modeling procedures may be found in Bolton and Meldahl (2). It is important that these procedures are reviewed before using the projection system, because many of the models were empirically derived and may not perform well outside the range of the data. MULTIPURPOSE FOREST PROJECTION SYSTEM FOR GEORGIA (GATWIGS) The growth and mortality models have been implemented into the TWIGS framework. TWIGS was originally developed by the U.S. Forest Service North Central Forest Experiment Station (1). This is a menu-driven program which allows the user to explore several silvicultural and economic alternatives. In its current version, this projection system is a PC-based program for IBM compatible machines with at least two floppy drives and 540K of memory. Input The data required to run this system are fairly straightforward and similar to that collected on a typical cruise. The table below is an example of a required input file (and is included as TREE.TXT on the data disk). This file may be created using any standard text editor (e.g., EDLIN, SPFPC). The file contains two types of records. AN EXAMPLE PLOT J. Doe Tract 400 491 491 110 611 611 802 802 802 802 812 812 812 812 820 521 552 621 131 131 S.W. 5.5 5.7 5.5 7.1 16.9 7.4 6.5 4.3 6.1 14.3 8.9 5.8 8.9 3.5 8.3 1.7 7.6 8.3 10.5 9.7 1990 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 20 0 16.0 10.0 9.0 28.0 55.0 25.0 22.0 0.0 20.0 36.0 29.0 17.0 30.0 0.0 26.0 0.0 20.0 30.0 45.0 41.0 40 75.0 PIE 6 ALABAMA AGRICULTURAL EXPERIMENT STATION The first type of record is the "header" or plot record. The fields are defined as: Columns 1-16 Property ID Field Stand ID Current year Current stand age Plantation status (0 = no; 1 = yes) 18-25 27-30 32-36 40 44-45 49-50 52-55 57-59 Tree count (total number of stems listed in the input file) Forest type Site index4 (base age = 50) Region Forest type codes closely follow those used by Forest Survey and are further defined in Appendix 1. Region is a three-digit code representing the physiographic region. These are defined as: LCP = Lower Coastal Plain UCP = Upper Coastal Plain PIE = Piedmont VAL = Valley and Ridge BLU = Blue Ridge Mountains The second type of record is the tree record. The fields for this record are defined as: Column 1-3 12-16 26-30 40-44 Field Species code Dbh Expansion factor (trees/acre represented by the stem) Bole length to a 4-inch d.o.b. (optional) Species codes follow those used by Forest Survey, and are further defined in Appendix 2. Bole length is an optional entry. EXECUTING GATWIGS Once the input file is created, TWIGS is fairly simple to execute. GATWIGS is designed to run off either a hard disk or two floppy drives. This system is distributed on two diskettes. The first diskette is known as the EXE disk and the second as'the DATA disk. If the user is operating off a hard disk, then both diskettes should simply be copied into a directory. To run GATWIGS on a dual floppy machine, place the EXE disk in drive A and the DATA disk in drive B. Now set the DOS prompt for drive A (A:/>) if using "Site index is a plot productivity value used for all species present. USER'S GUIDE TO FOREST PROJECTION SYSTEM 7 Read Tree List Set Run Options Set Economic Parameters Summary of Initial Stand Conditions Management Menu? y/n Economics Menu? y/n ) ) ... / _ -- Grow the Stand for One Cycle Summary of Stand Conditions Management Menu? y/n Economics Menu? y/n ) SRedo Management or Economics? v A. yesr ) ( Add Ingrowth? y/n Run Options? y/n ) (Change n Finished with All Growth Cycles? ) Print Summary Table D L FIG. 2. Flowchart of a TWIGS projection (6). the floppy drive method or for the appropriate directory (C:/GATWIGS>) if using a hard disk. Then simply type GATWIGS and hit return. TWIGS will then prompt the user for additional information. Figure 2 is a flow chart of a TWIGS program. Most op- ALABAMA AGRICULTURAL EXPERIMENT STATION tions and menus are straightforward. For a more in-depth exegesis on TWIGS the user is referred to the description of the original TWIGS program or to the latest documentation on TWIGS (1,6). It is important, due to the size of the output file, that when prompted for the location of the output file that it is assigned a location somewhere else than on the EXE disk. It is also important that DOS naming conventions are followed whenever such information is required. At most prompts, an example is given of the input required by TWIGS. SUMMARY After running TWIGS once the user will notice that many different options are available. These options should allow the user to explore myriad management strategies. The user is reminded that this projection system is based on a set of models, which have various assumptions. Information regarding the GATWIGS models and some of the known limitations is provided to the user at the start of each simulation. There are many reasons why these models may fail to accurately predict a given situation (4). Therefore, it is important that users familiarize themselves with how the models were constructed and think about what is input and output. For example, the system will allow the user to input a 30-inch dbh dogwood tree. The system will also grow the tree and calculate volumes. However, this tree is well outside the range of the data and any results should be suspect. Model validation is an on-going process. Due to the nature of the data used in deriving the models, this is an important process. It is also an involved process (3). Initial results suggest that overall the models adequately predict tree growth and mortality. Therefore, if used with some thought and caution, this projection system may prove to be a valuable tool. USER'S GUIDE TO FOREST PROJECTION SYSTEM LITERATURE CITED (1) BELCHER, D.M. 1982. TWIGS: The Woodsman's Ideal Growth Projection System. In: Microcomputers, a New Tool for Foresters. Proc. of a conf. sponsored by Purdue Univ. Dept. of Forestry and Natural Resources and the S.A.F. Systems Analysis and Inventory Working Groups. (Purdue University, West Lafayette, Ind., May 18-20, 1982.) BOLTON, R.K. AND R.S. MELDAHL. 1990. Design and Development of the Multipurpose Forest Projection System for Southern Forests. Ala. Agr. Exp. Sta. Bull. No. 603. BURK, T.E. 1986. Growth and Yield Model Validation: Have You Ever Met One That You Liked? Pages 35-39 in: Proceedings, Data Management Issues in Forestry. Forest Resource System Institute. Florence, Ala. HEPP, T.E. 1987. The Shortcomings of Models. Compiler 5(4):9-12. MELDAHL, R.S. 1986. Alternative Modeling Methodologies for Growth and Yield Projection Systems. Pages 27-31 in: Proceedings, Data Management Issues in Forestry. Forest Resource System Institute. Florence, Ala. MINER, C.L., N.R. WALTERS, AND M.L. BELLI. 1988. A Guide to the TWIGS Program for the North Central United States. USDA For. Ser. N. Cen. For. Exp. Sta., St. Paul, Minn., Gen Tech Rep. NC-125. TANSEY, J.B. 1983. Forest Statistics for Georgia, 1982. USDA For. Ser. S.E. For. Exp. Sta. Res. Bull. SE-69. WALKER, L.C. AND H.F. PERKINS. 1958. Forest Soils and Silviculture in Georgia. Ga. For. Res. Rep. No. 4. (2) (3) (4) (5) (6) (7) (8) USER'S GUIDE TO FOREST PROJECTION SYSTEM 11 APPENDIX 1. FOREST TYPE DEFINITIONS White Pine - Hemlock (Code 4)-Forests in which eastern white pine and hemlock, singly or in combination, comprise a majority of the stocking. Loblolly Pine Plantation(Code 5)-Forests in which loblolly pine was artifically regenerated with acceptable survival and comprises a plurality of the stocking. ShortleafPinePlantation(Code 6)-Forests in which shortleaf pine was artifically regenerated with acceptable survival and comprises a plurality of the stocking. LongleafPinePlantation(Code 7)-Forests in which longleaf pine was artifically regenerated with acceptable survival and comprises a plurality of the stocking. Longleaf Pine (Code 21)-Forests in which southern yellow pines, singly or in combination, comprise a plurality of the stocking, and in which longleaf pine contributes the most stocking of the pines. Slash Pine (Code 22)-Forests in which southern yellow pines, singly or in combination, comprise a plurality of the stocking, and in which slash pine contributes the most stocking of the pines. Loblolly Pine (Code 31)-Forests in which southern yellow pines, singly or in combination, comprise a plurality of the stocking, and in which loblolly pine contributes the most stocking of the pines. ShortleafPine(Code 32)-Forests in which southern yellow pines, singly or in combination, comprise a plurality of the stocking, and in which shortleaf pine contributes the most stocking of the pines. Virginia Pine (Code 33)-Forests in which southern yellow pines, singly or in combination, comprise a plurality of the stocking, and in which virginia pine contributes the most stocking of the pines. Redcedar (Code 35)-Forests in which redcedar comprises a plurality of the stocking. PondPine (Code 36)-Forests in which southern yellow pines, singly or in combination, comprise a plurality of the stocking, and in which pond pine contributes the most stocking of the pines. Pitch Pine (Code 38)-Forests in which southern yellow pines, singly or in combination, comprise a plurality of the stocking, and in which pitch pine contributes the most stocking of the pines. Oak-Pine (Code 40)-Forests in which hardwoods (usually upland 12 ALABAMA AGRICULTURAL EXPERIMENT STATION oaks) comprise a plurality of the stocking, but in which pines comprise 25 to 50 percent of the stocking. (Common associates include gum, hickory, and yellow poplar.) Oak-Hickory (Code 50)-Forests in which upland oaks or hickory, singly or in combination, comprise a plurality of the stocking, except where pines comprise 25 to 50 percent, in which case the stand would be classified oak-pine (Common associates include yellowpoplar, elm, maple, and black walnut.) Chestnut Oak (Code 52)-Forests in which chestnut oak (Quercus prinus) comprises a plurality of the stocking. Southern Scrub Oak (Code 57)-Forests in which blackjack, bluejack, turkey, dwarf post, and bear oak, singly or in combination, comprise a plurality of the stocking. Oak-Gum-Cypress (Code 60)-Bottomland forests in which tupelo, blackgum, sweetgum, oaks, or southern cypress, singly or in combination, comprise a plurality of the stocking, except where pines comprise 25 to 50 percent, in which case the stand would be classified oak-pine (Common associates include cottonwood, willow, ash, elm, hackberry, and maple.) Elm-Ash-Cottonwood (Code 70)-Forests in which elm, ash, or cottonwood, singly or in combination, comprise a plurality of the stocking (Common associates include willow, sycamore, beech, and maple.) USER'S GUIDE TO FOREST PROJECTION SYSTEM 1 13 APPENDIX 2. SPECIES CODE - COMMERCIAL TREES Yellow Pines 107 110 111 115 121 123 126 128 131 132 Sand pine Shortleaf pine Slash pine Spruce pine Longleaf pine Table-Mt. pine Pitch pine Pond pine Loblolly pine Virginia pine Fraser fir Atlantic white-cedar Pinus clausa Pinus echinata Pinus elliottii Pinus glabra Pinus palustris Pinus pungens Pinus rigida Pinus serotina Pinus taeda Pinus virginiana Other Softwoods 010 043 060 090 129 221 222 241 260 Eastern redcedar Red spruce White pine Baldcypress Pondcypress Northern white-cedar Eastern hemlock Abies fraseri Chamaecyparis thyoides Juniperus virginiana Picea rubens Pinus strobus Taxodium distichum var. distichum Taxodium distichum var. nutans Thuja occidentalis Tsuga canadensis Soft Hardwoods 313 316 317 330 460 555 580 601 611 621 651 652 653 691 Boxelder Red maple Silver maple Buckeye Hackberry Loblolly-bay Silverbell (in mts.) Butternut Sweetgum Yellow-poplar Cucumbertree Magnolia Sweetbay Water tupelo Acer negundo Acer rubrum Acer saceharinum Aesculus spp. Celtis occidentalis Gordonia lasianthus Halesia spp. Juglans cinerea Liquidambar styraciflua Liriodendron tulipifera Magnolia acuminata Magnolia spp. Magnolia virginiana Nyssa aquatica 14 -r ALABAMA 14 ALABAMA AGRICULTURALEXPERIMENT STATION AGRICULTURAL EXPERIMENT STATION 693, 694 731 740 762 920 950 970 Blackgum (upland) Blackgum (lowland) American sycamore Cottonwood Black cherry Willow American basswood Elm Nyssa sylvatica Nyssa sylvatica Platanus occidentalis Populus spp. Prunus serotina Salix spp. Tilia americana Ulmus spp. Hard Hardwoods 311 318 370 371 400 491 521 531 540 552 591 602 680 802 804 806 812 813 817 820 822 823825 826 827 830 831 832 833 834 Florida maple Sugar maple Birch (except yellow) Yellow birch Hickory Flowering dogwood Persimmon (forest grown) American beech Ash Honeylocust American holly Black walnut Red mulberry White oak Swamp white oak Scarlet oak Southern red oak Cherrybark oak Shingle oak Laurel oak Overcup oak Bur oak Swamp chestnut oak Chinkapin oak Water oak Pin oak Willow oak Chestnut oak Northern red oak Shumard oak Acer barbatum Acer saccharum Betula spp. Betula alleghaniensis Carya spp. Cornus florida Diospyros virginiana Fagus grandifolia Fraxinus spp. Gleditsia triacanthos flex opaca Juglans nigra Morus rubra Quercus alba Quercus bicolor Quercus coccinea Quercus falcata Quercus falcata var. pagodaefolla Quercus imbricaria Quercus laurifolia Quercus lyrata Quercus macrocarpa Quercus michauxii Quercus muehlenbergii Quercus nigra Quercus palustris Quercus phellos Quercus prinus Quercus rubra Quercus shumardii USER'S USER'S GUIDE TO FOREST PROJECTION SYSTEM GUIDE TO FOREST PROJECTION SYSTEM 15 15 835 837 838 901 Post oak Black oak Live oak Black locust Quercus stellata Quercus velutina Quercus virginiana Robinia pseudoacacia Miscellaneous Species 310 315 319 341 352 391 421 451 471 521 548 581 641 660 661 692 701 711 712 721 722 760 807 816 819 824 840 841 899 931 999 Chalk maple Striped maple Mountain maple Ailanthus Serviceberry Blue beech American chestnut Catalpa Eastern redbud Persimmon (field grown) American mt. ash Carolina silverbell (except mts.) Osage-orange Domestic fruit (apple etc.) Chinaberry Ogeechee gum Eastern hophornbeam Sourwood Royal paulownia Redbay Planer-tree (water-elm) Fire cherry Bluejack oak Bear oak Turkey oak Blackjack oak Dwarf post oak Dwarf live oak Other scrub oaks Sassafras Other miscellaneous trees Acer saccharum var. leucoderme Acer pensylvanicum Acer spicatum Ailanthus spp. Amelanchier spp. Carpinus caroliniana Castaneadentata Catalpa spp. Cercis canadensis Diospyros virginiana Pyrus americana Halesia carolina Maclura pomifera Malus spp. Melia azedarach Nyssa ogeche Ostrya virginiana Oxydendrum arboreum Paulownia tomentosa Persea borbonia Planera aquatica Prunus pensylvanica Quercus incana Quercus ilicifolia Quercus laevis Quercus marilandica Quercus stellata spp. Quercus virginiana spp. Quercus spp. Sassafras albidum i~~i~lk'.C', LLULC l _I1 i With an agricultural research unit in every major soil area, Auburn University serves the needs of field crop, livestock, forestry, and horticultural producers in each region in Alabama. Every citizen of the State has a stake in this research program, since any advantage from new and more economical ways of producing and handling farm products directly benefits the consuming public. 0 0 7 8 0 0 06 0 o Q9 ® Main Agricultural Experiment Station, Auburn. I E. V. Smith Research Center, Shorter. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Tennessee Valley Substation Belle Mina Sand Mountain Substation, Crossville North Alabama Horticulture Substation, Culiman Upper Coastal Plain Substation, Winfield Forestry Unit. Fayette County Chilton Area Horticulture Substation, Clanton Forestry Unit. Coosa County Piedmont Substation. Camp Hill Piant Breeding Unit Tallassee Forestry Unit, Autauga County Prattville Experiment Field, Prattville Black Belt Substation. Marion Junction The Turnipseed-Ikenberry Place, Union Springs Lower Coastal Plain Substation. Camden Forestry Unit, Barbour County Monroevilie Experiment Field, Monroeville Wiregrass Substation, Headland Brewton Experiment Field, Brewton Solon Dixon Forestry Education Center. Covington and Escambia counties 20 Ornamental Horticulture Substation, Spring Hill 21 Gulf Coast Substation. Fairhope