Land Use/Land Cover Legend

for use with grids depicting
Willamette Basin LU/LC ca.1990 and Future Scenarios 2000-2050,
products of the PNW-ERC Willamette River Basin Alternative Futures Study.

November 22,  2000

OSU/FSL TM Classes values are those from the 40 class grid;
Agricultural "B&B" classes are from the agricultural land use layer provided by John Bolte and Pat Berger of OSU/Bioresource Engineering.
Forest disturbance layer is from Cohen et al, Forestry Sciences Laboratory, OSU.

DU = Dwelling Units; 1 grid cell = 30 meters

1 Residential  0-4 DU/ac a) Within ugbs in all counties except Yamhill and Columbia (where digital taxlot data in GIS format were not available), urban landuse categories 1-6, and 8 were derived primarily from taxlot and census data. The taxlot data provided parcel descriptions of landuse which were mapped into categories residential, commercial, industrial, vacant and "other".

The residential parcels were compared with the US census household density description and converted to a household density: 1 = 0-4 DU/acre, low density; 2 = 4-9 DU/acre, medium density; 3 = 9-16 DU/acre, medium high density; 4 = >16 DU/acre, high density.

"Other" represents unknown uses, and parcels with improved farm and forest uses. Since the type of improvement on these parcels is unknown and is not spatially located within the generally large area of these parcels, a combination of landuse/landcover was used to represent these parcels in the grid. If a low or medium built category of landcover (TM) is present, this is mapped into a residential density qualified by census data; a high built category is mapped into legend category 7 (commercial/industrial). The remaining vegetative landcover is retained in place in these "other" parcels.

"Vacant" parcels, so designated in taxlot data, are depicted by their landcover, with any TM built categories being collapsed into legend category 11.

b).Within ugbs in Yamhill and Columbia counties: FSL TM classes 34-36 were remapped into "residential" and then further qualified into household density by use of census data. Landcover class 34 (FSL) was remapped into commercial/industrial (category 7).

2 Residential 4-9 DU/ac  Within ugbs only. See 1 above
3 Residential  9-16 DU/ac Within ugbs only. See 1 above
4 Residential  >16 DU/ac Within ugbs only. See 1 above
5 Vacant For modeling purposes: within ugbs only and used only temporarily;  not found in these landuse/landcover grids. As described in 1. above, vacant lands are located by taxlot information and are represented in these grids by their landcover with any TM built categories remapped as 11.
6 Commercial Within ugbs only. See 1 above
7 Comm/Industrial Within ugbs only: primarily used in Yamhill and Columbia counties where no taxlot data are available, but also present in other counties where taxlot parcel information was judged as "other" (see 1 above); derived from TM class 26 - Built high density. 
8 Industrial Within ugbs only. See 1 above
9 Industrial & Comm. Within ugbs only. Used in modeling to identify urban locations in which both industrial and commercial uses simultaneously occupy a grid cell - a mixed use zone.
10 Residential & Comm. Within ugbs only. A modeled urban mixed use zone where both residential and commercial uses simultaneously occupy a grid cell.
11 Urban non-vegetated unknown Derived from FSL TM classes 34 - 36. Within UGB's only, and only in areas defined by taxlot information as vacant, civic/open space, or road, railroad right of ways and rivers.
16 Rural structures Outside ugbs only. Derived from scanned USGS 7.5' quadrangle maps.
18 Railroad Class 18 of ODOT county map sheets; 1 cell wide grid.
19 Primary roads  ODOT interstate Highways (functional road class 50); 3 grid cells wide.
20 Secondary roads ODOT principal arterials (functional road class 51); 2 grid cells wide.
21 Light duty roads ODOT minor arterials and major/urban collectors (functional road class 52, 53); 1 grid cell wide. Within ugbs this category also includes ODOT local roads (class 12, 1 cell wide) in small cities in Yamhhill or Columbia Counties, or, taxlot parcel -derived roads (including rights of way) in cities in other counties.
24 Rural non-vegetated unknown FSL TM "built" classes outside of ugbs are set to "rural  non-vegetated unknown." According to Doug Oetter (pers. comm, April 1999), the FSL TM built density classes (TM classes 34-36) may include fallow land, rock, bare ground, gravel pits, gravel bars, roofs, roads, etc. It is assumed that the rural structure data, the ODOT roads, etc (as described above) are better descriptors of the land uses that we wish to isolate (more confidence) than the TM built categories. Note that gravel pits and mines will most likely be in this category (except for any that fall inside the mainstem Willamette River active channel coverage, as described below).
29 Main channel non-vegetated  Within Willamette River active channel, those cells having FSL TM classes 34-36. Gravel bars, bridges, revetments, etc. that lie inside the river channel boundary will be included here.
32 Stream orders 5-7 Gridded 1 cell wide from RIVREACH_2, plus gridded 1995 Willamette River active channel polygons.
33 Permanent lentic water FSL TM class 37.
39 Topographic Shadow FSL TM class 40
40 Snow FSL TM class 39
42 Barren FSL TM class 38
49 Urban tree overstory Replaces the TM category "orchard" (FSL class 20) within ugbs (comparison of known areas shows high confusion of orchards with street trees);  also, potentially in future scenarios, a  developing tree cover in areas urbanized in prior time steps.
51 Upland Forest open FSL TM class 22
52 Upland Forest Semi-closed mixed FSL TM class 24
53 Forest Closed hardwood  FSL TM class 26
54 Forest Closed mixed  FSL TM class 27
55 Upland Forest Semi-closed conifer  FSL TM class 25
56 Conifers 0-20 yrs  FSL TM class 28; forest disturbance layer for 1972-1988
57 Forest closed conifer 21-40 yrs FSL TM class 29
58 Forest closed conifer 41-60 yrs. FSL TM class 30
59 Forest closed conifer 61-80 yrs FSL TM class 31
60 Forest closed conifer 81-200 yrs FSL TM class 32
61 Forest closed conifer older than 200 yrs FSL TM class 33
62 Upland Forest Semi-closed hardwood FSL TM class 23
66 Hybrid poplar B&B class 11
67 Grass seed rotation B&B class 8
68 Irrigated annual  rotation B&B  class 6
71 Grains (B&B )
72 Nursery B&B  class 5
73 Berries & Vineyards  B&B  class 2;  FSL TM class 1
74 Double cropping  FSL TM class 2
75 Hops FSL TM class 3
76 Mint  FSL TM class 4
77 Radish seed  FSL TM class 5
78 Sugar beet seed FSL TM class 6
79 Row crop FSL TM class 7
80 Grass  FSL TM class 8
81 Burned grass FSL TM class 9
82 Field crop FSL TM class 10
83 Hayfield B&B class 9;  FSL TM class 11
84 Late field crop FSL TM class 12
85 Pasture  B&B class 10;  FSL TM class 13
86 Natural grassland  FSL TM class 14
87 Natural shrub FSL TM class 15
88 Bare/fallow FSL TM class 16
89 Flooded/marsh  FSL TM class 17
90 Irrigated perennial B&B class 4;  FSL TM class 18
91 Turfgrass FSL TM class 19. Within ugbs, this is mostly golf course fairways,and is treated as undevelopable; it overlies all urban landuse categories. Outside ugbs, this is mostly turfgrass, or highly irrigated/nutrient-rich crops. 
92 Orchard B&B class 1; FSL TM class 20 outside of urban areas.
93 Christmas trees B&B class 3;  FSL TM class 21
95 Conifer Woodlot B&B class 12
98 Oak savanna  .
101 Wet shrub .
102 Unknown .

modified Wednesday, November 22, 2000 ISE/UO, dd