2015-12-07_GENERAL DOCUMENTS - M1973007

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VEGETATION INFORMATION currently is prohibited for planting in Colorado, although its removal as a noxious weed is not mandatory. Within the affected land the vegetation is strikingly different. The affected land, except for the western edge, is divided into a series of very regular, rectangular cells with the long dimension on a more or less east/west line. These cells are surrounded by low berms a few feet high. The cells are effectively closed basins. Perhaps someone once attempted to farm catfish here or established evaporation cells for some other purpose. The general slope of the land is to toward the southeast, but the gradient is very slight with the eastern edge only a few feet lower than the western edge. Thus rainwater tends to accumulate on the eastern edge of the cells. In those locations stronger grass growth occurs, especially in the eastern set of cells. The western set of cells shows much less grass growth on the low side. It is also likely that the eastern end of the eastern set of cells receives a slight amount of ground water support as it is known that the ground water is quite shallow east of these cells. However,because the ground water elevation declines rapidly toward the west, this ground water support, if it occurs at all, only influences a narrow zone on the eastern end of the eastern set of cells. Throughout the remainder of the cells growth is supported by precipitation alone. The grasses in these wetter areas are primarily Reed-Canary Grass in the wettest areas, but this quickly transitions to the more common Needlegrass that occurs throughout the rest of the area. In a few places, cattails can be found, but they are small individuals obviously living on the very fringe of their tolerance curve for the moisture factor. These areas are not considered wetland as there is little evidence that the groundwater frequently gets close to the surface. More likely, the plants that are not uncommon in wetlands, simply have very deep root systems. Over the remainder of the site the dominant species is Kochia, an annual weed. In many places these weeds are very dense and large, but in more sandy soils they tend to be more sparse and smaller. Mixed in with the weeds is a minor component of Needlegrass (probably Stipa comata). The grass component is rarely more than 10% of the composition. In a few places Blue Grama and Western Wheatgrass can also be found along with other very sparse growths of introduced grass species. Although Canada Thistle is very abundant in a few areas adjacent to wetlands outside the rectangular cells, it is very rare in the affected land. This is probably due to a combination of the soils being too dry and the competition from the other weeds. West of the rectangular cells the land rises fairly rapidly to a high berm that probably formed the western edge of the basin. This area is also strongly dominated by the Kochia with the grass component being even less than it is in the rectangular cells. This strong dominance of annual weeds, considering the many years since this was a reservoir site, is of some concern. It is likely that the soils in this basin contain high levels of nitrogen that tend to maintain this very low level successional vegetation. Although there are some signs of a slow shift toward more grass as the nutrients are consumed, that shift is very slight and perhaps more an illusion than a reality. Where the grasses are the strongest the soil is clearly more coarse with a high content of Daniels Sand Pit#2 Amendment (2008) Exhibit I Page 4 of 6