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311 lines
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>A Brief History of GRASS</TITLE
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>The Geographic Information Systems: GRASS HOWTO</TH
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CLASS="SECT1"
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><A
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NAME="HISTORY"
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>3. A Brief History of GRASS</A
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></H1
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><P
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> In the early 1980s the U. S. Army Corps of Engineers' Construction
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Engineering Research Laboratory (USA/CERL) in Champaign, Illinois, began
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to explore the possibilities of using Geographic Information Systems to
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conduct environmental research, assessments, monitoring and management
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of lands under the stewardship of the U. S. Department of Defense. Part
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of the motivation for this action was new responsibility for the
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environment encoded into the National Environmental Policy Act of the
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late 1970s.
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</P
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><P
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> Bill Goran of USA/CERL conducted a survey of available GISs, assuming
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that he could find several systems capable of environmental analysis,
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from which he could select one or more to recommend for use by CERL and
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perhaps others in the Department of Defense. However, he was surprised
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to find no GIS that satisfied his needs. What started as a selection
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process turned into a design exercise for his own GIS development
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program.
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</P
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><P
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> USA/CERL hired several programmers, and began by writing a hybrid
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raster-vector GIS for the VAX UNIX environment. This made the team one
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of the first to seriously develop GIS for UNIX. Though they still faced
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challenges with different versions of UNIX, they developed procedures of
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coding in ANSI standard UNIX, avoiding "tweaking" the code toward any
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particular vendor-specific flavor of UNIX.
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</P
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><P
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> GRASS developed a programming style characterized by:
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</P
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><P
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></P
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><UL
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><LI
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><P
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> Use of UNIX libraries where possible, plus the creation of GRASS
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libraries for repeated GIS-specific acts such as opening raster
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files that might be compressed (by run-length encoding) or not.
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</P
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></LI
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><LI
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><P
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> The ability to handle both major GIS data types: raster and vector.
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</P
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></LI
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><LI
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><P
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> The favoring of raster data processing, as scientific analysis was
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easier to encode with raster (than for vector) data models.
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</P
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></LI
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><LI
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><P
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> The ability to handle raster grids of mixed grid sizes in the same
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data base. This was a departure from raster's image processing
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tradition of requiring identical (and perfectly registered) grid
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cell arrays in each and every data layer.
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</P
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></LI
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><LI
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><P
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> The ability to handle raster grids with different areas of
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coverage. Again, this was a departure from raster tradition of
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having all grids be identical in geographic coverage.
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</P
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></LI
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><LI
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><P
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> The ability to run-length encode raster data files, in order to
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greatly reduce file sizes of most files.
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</P
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></LI
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><LI
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><P
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> The separate structure of reclassification files. Such files
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merely contained a look-up table noting the previous and new
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classes. This is MUCH more compact than replicating the original
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grid with different numerical values. A reclassified file of a
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100x100 km square area of 10 metre grid cells would be a few
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hundred bytes, rather than 100 megabytes of uncompressed 8-bit
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raster data.
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</P
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></LI
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><LI
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><P
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> The acceptance of de-facto standard data models. While competitors
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created cumbersome (and in many cases secretive) data formats,
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GRASS accepted the de-facto standard Digital Line Graph vector
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format and unheaded binary raster grid format. GRASS later
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abandoned DLG as its internal vector file format, and let its
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raster format evolve. However, DLG and the unheaded binary raster
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grid are still routinely handled formats for GRASS, and its new
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formats are as open as its previous ones.
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</P
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></LI
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><LI
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><P
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> GRASS code was managed in several directories. Initial
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contributions were placed in the src.contrib directory. More solid
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code was moved to the src.alpha directory. After remaining in the
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src.alpha for one full release cycle, the code, with resultant bug
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fixes, moved to the most honorable level, the src directory.
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</P
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></LI
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></UL
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><P
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>
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GRASS was overseen by three levels of oversight committees. USA/CERL
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kept the ultimate responsibility for GRASS. It implemented most GRASS
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development, and carried out the day-to-day management of GRASS testing
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and release. The GRASS Interagency Steering Committee (GIASC),
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comprised of other Federal agencies, met semi-annually to review
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development progress, and evaluate future directions for GRASS.
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(Academic and commercial participants in GRASS also attended GIASC
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meetings; only part of each meeting was "Federal-Agencies-only." GRASS
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eventually became nominally and officially a "product" of the GIASC,
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though everyone recognized USA/CERL's leadership role. The GRASS
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Military Steering Committee met periodically to review the progress of
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GRASS in serving its original intent: meeting the Department of
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Defense's needs to evaluate and manage the environment of military
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lands.
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</P
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><P
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> The public interacted with CERL and GIASC through USA/CERL's GRASS
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Information Center. GRASS Beta testing was very widespread, and quite
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intensive for the leading users of GRASS. Several leading users, such
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as the National Park Service and the Soil Conservation Service, selected
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GRASS as its prime or only GIS. They made significant commitments to
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enhance and test GRASS, yet considered this investment well worth their
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while. They said that they had more influence over the direction of
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GRASS than they would over any known alternative system. They also felt
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that, despite their major efforts and expenses in supporting GRASS, they
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had a bargain in relevant power for the dollar.
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</P
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><P
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> Several universities adopted GRASS as an important training and research
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environment. Many conducted short-courses for the public, in addition
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to using GRASS in their own curricula. Examples of such leading
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academic users of GRASS are Central Washington University, The
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University of Arkansas, Texas A & M University, The University of
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California at Berkeley, and Rutgers University.
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</P
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><P
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> Though GRASS received some criticism (some say) for being so good and so
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public, it was also reputedly borrowed from liberally by some developers
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of other systems. Though the first group might have viewed it as unfair
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competition, the second group may have noted that it was not copyright,
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and was a valuable testbed for GIS concepts. GRASS received an award
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from the Urban and Regional Information Systems Association (URISA) for
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quality software in 1988.
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</P
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><P
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> As CERL and GRASS evolved through the late 1980s and early 1990s, CERL
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attempted to cut overhead costs associated with supporting the public
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domain version. It created and initially funded the Open GRASS
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Foundation, in cooperation with several of the leading users of GRASS.
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The Open GRASS Foundation has since evolved into the Open GIS
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Consortium, which is aiming for more thorough interoperability at the
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data and user interface level, but appears not to be taking advantage of
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the major open GIS testbed (GRASS).
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</P
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><P
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> In 1996 USA/CERL, just before beginning the beta testing for GRASS
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version 5.0, announced that it was formally withdrawing support to the
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public. USA/CERL announced agreements with several commercial GISs, and
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agreed to provide encouragement to commercialization of GRASS. One
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result of this is
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<A
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HREF="http://www.las.com/grassland/"
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TARGET="_top"
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><I
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CLASS="CITETITLE"
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>GRASSLANDS</I
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></A
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>,
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a commercial adaptation of much of GRASS. Another result is a migration of
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several former GRASS users to COTS (Commercial Off-The-Shelf) GISs.
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However, GRASS' anonymous ftp site contains many enhancements to the
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last full version 4.1 release of GRASS. Many organizations still use
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GRASS feeling that, despite the lack of a major release in five years,
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GRASS still leads the pack in many areas.
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</P
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>What Is GRASS?</TD
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>A Re-Invogorated GRASS Management Model</TD
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