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SOIL MAPPING The U.S.D.A. Soil Conservation Service publication Soil Surygy of San Joaquin County. California indicates the presence of Capay, El Solyo,Vernalis and Zacharias soil series on the subject property. This soil study confirms the presence of the listed soil series. However, the boundaries of the soil series appear to be different than those on the S.C.S. map. The objective of the S.M.A.R.A. guidelines is to catalog the existing soil resources. Sufficient work was performed in this soil study to meet that objective with an emphasis on identifying prime and non-prime agricultural soils. Re-drawing the existing soil series boundaries was not a primary consideration of this study and is not required by S.M.A.R.A. Soil type boundaries were adjusted only where sufficient data was available. The balance of the soil boundaries were left as originally mapped. Xerofluents were not identified on this parcel in the U.S.D.A. soil survey, however, the backhoe excavations revealed the existence of Xerofluents in a north west area on the property. Thus,the soil type boundaries on the Soil Conservation Service map were adjusted to include the Xerofluvents (see Appendix A Soil Map). Each of the mapped soil type areas may have small inclusions or complexes of other soil types within them. RESULTS AND DISCUSSION SOIL PHYSICAL CHARACTERISTICS AND PROFILES Soil physical characteristics impact root development and plant growth. Some physical properties to consider are bulk density, soil consistence, depth and texture (see Appendix B Glossary of Terms). The existing soils have a friable consistence for the most part, however,the subsoils observed in Sites 9 and 10 were firm or compacted. Firm or compacted subsoils can limit root development and water percolation. The soil depth in the existing soils is sufficient at most Sites for agricultural uses. The subsoils at Sites 7 and 8 (Xerofluents) are gravelly and highly stratified. This would limit rooting depth, water percolation and productivity of deep rooted crops. The location of sites with stratified or firm subsoils are indicated on the soil maps (see Appendix A). Soil structure is typically crumb in the plow layer(AP horizon), blocky or prismatic in the B _ horizons (mid to lower profile) and structureless (massive) in the C horizons (deepest layers, parent materials). The soil structures observed at each of the selected backhoe excavation sites are recorded in the soil profile descriptions (See Appendix B). The Capay series is a deep, moderately well drained, clay loam textured soil above a gravelly clay loam . The El Solyo complex observed on the subject property is a deep, well drained, clay loam surface soil over a loamy subsoil. The Vernalis series consists of a very deep, well drained loam to clay loam surface soil underlain by a loam subsoil. A gravelly sandy loam or gravelly loam layer is beneath the loam subsoil. 5