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ERC West Farm Pit Expansion Project Site
<br /> Aquatic Resource Delineation Report
<br /> 4.0 EXISTING CONDITIONS
<br /> 4.1 LANDSCAPE SETTING
<br /> The survey area is situated within the Great Plains Ruderal Grassland and Shrubland (Comer et al. 2003) at an
<br /> approximate elevation of 3,600 feet above mean sea level (AMSL). The survey area consists of agricultural lands
<br /> currently farmed as alfalfa. Surrounding the survey area are more central irrigation pivoted alfalfa fields. Land
<br /> within the WFP Facility consists of the active Prowers Aggregate West Farm Pit processing facility with office
<br /> buildings, material stockpiles, and processing equipment, completely denuded of any natural features. Lands
<br /> located outside of the survey areas but within the overall WFP Facility are not included in this ARD.
<br /> The Great Plains Ruderal Grassland and Shrubland is found in the Great Plains from north of the U.S.-Canadian
<br /> border to extreme northern Mexico. It is dominated by exotic, invasive grasses, forbs, or, in the south, deciduous
<br /> shrubs. These species can become abundant after significant disturbance, often associated with agricultural
<br /> activities,or a disruption of natural disturbance regimes. Common disturbances which favor establishment of this
<br /> macrogroup include long-term, heavy grazing, planting exotic species for livestock forage, plowing land and then
<br /> abandoning it,and a disruption of the natural fire regime.Vegetation cover varies from low to very high.Abundant
<br /> species vary greatly in this macrogroup, depending on the geographic location, seed sources, and nature of land
<br /> use. Common species in the north include crested wheatgrass (Agropyron cristatum), smooth brome (Bromus
<br /> inermis), field brome (eromus arvensis), cheatgrass(Bromus tectorum), common couch (Elymus repens) (on more
<br /> moist sites), timothy grass (Phleum pratense), Kentucky bluegrass (Poo protensis), and intermediate wheatgrass
<br /> (Thinopyrum intermedium). In the south,yellow bluestem (Bothriochloa ischoemum var. songarico), buffalo grass
<br /> (Bouteloua dactyloides)(a native but can be dominant on overgrazed rangeland), Kleberg's bluestem(Dichanthium
<br /> annulatum), bufflegrass (Pennisetum ciliare), and the shrubs Roosevelt weed (Baccharis neglecta), downy
<br /> hawthorn (Crataegus mollis), green hawthorn (Crataegus viridis), and prairie leaf sumac (Rhus lanceolata) can be
<br /> common. Texas snakeweed (Gutierrezia texano) and prairie broomweed (Amphiachyris dracunculoides) are often
<br /> extremely abundant on overgrazed sites in Texas. Across the range the forbs ragweed (Ambrosia spp.), common
<br /> wormwood (Artemisio obsinthium), musk thistle (Carduus nutans), knapweed (Centourea spp.), Canadian thistle
<br /> (Cirsium arvense), field bindweed (Convolvulus arvensis), wild teasel (Dipsocus fullonum), and leafy spurge
<br /> (Euphorbia esula)can be common.This macrogroup also includes native upland shortgrass prairie areas dominated
<br /> by invasive honey mesquite(Prosopis glandulosa).This macrogroup can be found on mesic to dry sites on a variety
<br /> of soils where disturbance regimes have been altered sufficiently to allow the establishment of the exotic species.
<br /> Aquatic Resource habitats within the survey area are characterized by the Great Plains Flooded &Swamp Forest
<br /> ecological system (Comer et al. 2014). This macrogroup is composed of woodlands and forests found along large
<br /> to small rivers in the western and central Great Plains from southern Canada to the Texas panhandle. Eastern
<br /> cottonwood (Populus deltoides) is the most common tree and may be nearly the only species in the overstory in
<br /> some stands. Other common trees are boxelder maple (Acer negundo), green ash (Fraxinus pennsylvanica), black
<br /> willow (Solix nigra), peachleaf willow (Solix amygdaloides), and, in the southeastern portion of this macrogroup's
<br /> range, sugarberry (Celtis laevigata) and American sycamore (Platanus occidentalis). The shrub and herbaceous
<br /> layers are much more diverse than the canopy across the range of this macrogroup with no single species common
<br /> throughout. Typical shrubs include silver sagebrush (Artemisia cana), dogwood (Cornus spp.), willow (Solix spp.),
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