Vegetation Classification and Mapping Project Report - USGS

G22
B19 Alkali Sacaton - Blue Grama Herbaceous Vegetation
Figure.G37..Ground.photo.for.map.class.B19,.
Alkali.Sacaton.-.Blue.Grama.Herbaceous.
Vegetation.
Figure.G38..Photosignature.for.map.class.
B19,.Alkali.Sacaton.-.Blue.Grama.Herbaceous.
Vegetation.
Location: Alkali Sacaton - Blue Grama Herbaceous Vegetation occurred throughout the project area. Three
main areas of this association occurred, including the northeastern section of the project area, the central
neck area between the Puerco River and Interstate 40, and east of The Flattops. This map class was almost
equally distributed between the NPS land and the project environs.
Photosignature: Grass species were not easily identifiable on the aerial photography. The photosignature
appeared to have a smooth texture and depending on the herbaceous cover, the color appeared to have a
green to grayish brown color. This map class was difficult to distinguish from the most of the other shortgrass
herbaceous map classes. It was most commonly identified during the photointerpretation from the
field data collection and extrapolated from these locations.
Plant communities
Sporobolus airoides - Bouteloua gracilis Herbaceous
Vegetation
Group map class Inter-Mountain Basins Semi-Desert Grassland (1 of 7)
Management map class Alkali Sacaton Steppe and Mixed Grasslands (1 of 8)
Macrogroup map class
Inter-Mountain Basins Semi-Desert Grassland and
Steppe (1 of 17)
Number of map units in park 24
Number of map units in park & environs 42
Number of map units less than 0.5 ha 12 (0.9% of total map class area)
Area of map class in park
284.2 ha / 702.3 ac
Total area of map class
377.1 ha / 931.8 ac
Proportion of land cover in park 0.7%
Proportion of map class in project environs 24.6%
Base map class accuracy user 37.5 (20.8 - 57.8), producer 15.0 (8.0 - 26.5)
Group map class accuracy user 69.3 (60.8 - 76.7), producer 44.9 (38.0 - 51.9)
Management map class accuracy user 73.0 (66.9 - 78.3), producer 64.0 (58.0 - 69.5)
Macrogroup map class accuracy user 93.0 (90.1 - 95.0), producer 77.2 (73.3 - 80.6)
Documentation for base map class
7 2003 relevés, 6 1996 relevés, 41 AA observation sites
Vegetation Classification and Distribution Mapping Report: Petrified Forest National Park