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Review Draft Eastern Gateway Wetland Restoration Site -- Annual Report <br /> develop to maturity (many species take several years before reaching flowering <br /> size), but the start is good. While non - native species are common, especially in <br /> Macroplot #3, many of these species may be relatively ephemeral colonizers of <br /> bare habitats that may decrease in frequency and cover as the native perennials <br /> get established. <br /> The emergent meadow community, represented by Macroplot #2, appears to be <br /> even more successfully established, given the prominence of native species in <br /> the sampling data. Though species diversity is somewhat lower in this <br /> macroplot (it was too deeply inundated for many of the wet prairie perennial <br /> forbs), native species were strongly dominant. It appears quite likely that native <br /> wetland vegetation will become well established in this portion of the site as <br /> long as invasive species such as reed canary grass can be kept out. <br /> 11. Soils <br /> The primary goal of the excavation and grading was to remove all of the fill <br /> material from the site and excavate to the original (native) soil surface. It was <br /> anticipated that these native soils would exhibit hydric characteristics, and <br /> would be a suitable substrate for re- establishment of wetland conditions. <br /> During construction, it was clearly evident where the boundary was between <br /> the fill and the native soil, due to differences in soil chroma and hue. The fill <br /> was primarily upland soil with a chroma of 3 or higher, while the native soil <br /> was darker and had a lower chroma (typically 10YR 2/1). <br /> The post - construction soils are quite similar to the native soils mapped in the <br /> Lane County Soil Survey (Patching, 1987). While no detailed post - construction <br /> soil mapping was done, it was evident from qualitative observations that most of <br /> the site was similar to Natroy silty clay loam (hydric), the unit that is mapped <br /> for most of the site. Typically, the site supports a rather thin surface layer of <br /> silty clay loam over a subsurface clay layer. This surface layer is sufficiently <br /> textured (silt loam or silty clay loam) to be a suitable medium for growth of <br /> roots of herbaceous plants. <br /> Two other soil units are mapped for the site, Courtney gravelly silty clay loam <br /> • (hydric) and Holcomb silty clay loam. The Courtney -soil is mapped for the <br /> north- central portion of the site, and includes the area where vegetation <br /> sampling Macroplot #2 was established. The top 15 inches of this soil is a silty <br /> clay loam with a substantial gravel component, which explains the abundance of <br /> alluvial cobbles which were found on the surface after excavation. Holcomb <br /> silty clay loam is mapped for the SE portion of the site, and is represented in <br /> part by the area where vegetation sampling Macroplot #3 was established. <br /> Page 12 <br />