Recent Sediments

Original Soils

12/8/06

The original soils pictured here were covered with 6” to 8” of recent sedimentation from an adjacent road overpass construction project.  In this view, the clays in these overlying sediments have contracted and consequently the soil has pulled away from the buried tree stem. 

12/8/06

12/8/06

Thus, the tree looks like a pencil stuck in the ground (i.e., the tree’s natural slight butt swell is buried ). 
 

Sediments Covering the Original Soil Surface

Sediments Covering the Original Soil Surface

The soil materials in this auger sample are representative of the sediments covering the original soil surface on this site.  I didn’t characterize the high chroma sediments here (this was a recon auger sample), but they appear to be approximately 10YR 5/4-5/6 to 7.5YR 5/4 to 5/6.  The texture was probably silty clay loam to sandy clay.

The low chroma mineral materials shown in this photo were located below the high chroma sediments and may have been either: 1) the original soil surface; or, 2) high chroma sediments that have been reduced and had a recent color change.
 

Low Chroma Mineral Materials

Low Chroma Mineral Materials

From a nearby auger hole used to characterize a data point in this community, the “original” soil (i.e., the now buried soil) was:  0” to 2” BSS – 10YR 2/1, mucky silt loam; 2” to 24” BSS – 10YR 2/1, muck: 24” to 48” BSS – N2/0, muck.  The soils were organic and hydric.  Free water stood at the surface in the data point auger hole, and the soils were saturated from the surface to 48” BSS.

The plant community was a Forested Bayhead dominated by: Cliftonia monophylla (T & S/S), Magnolia virginiana (T), Ilex coriacea (S/S), Smilax laurifolia (WV), and Lyonia lucida (H). The Dominance Test = 100%, and the Fac-Neutral Test = 6:0.

There are several features about this site (some shown here, some not) that should alert one to the prospect that some characteristics of the area may have been altered.  On a landscape level, the newly constructed highway overpass with its sediment fence and adjacent sediment splay should provide the first clue.   The pencil tree and its clay collar soils gap should also activate one’s environmental radar.  Upon augering and examining a sample from the upper layer of soil, the resulting high chroma materials should shift the tentative “Has something happened here?” question to the definitive “What has happened here?”

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