11-19-2007 Planning Commission Packet

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_ � Some pedons have AB horizons. The Btg horizon has a matr'v: with hue of 1OYR to SY, vaIue of 3 to 5, value of 3 is only in the upper part, and chroma of 1 or 2. Some pedons have a BA horizon. The B horizon typically is silty clay loam or clay loarri but ranges to loam in the lower part: The upper 20 inches of the argillic:horizon averages between?8 to 35 percent clay and exceeds 15 percent fine sand and coarser. The B/A clay ratios range from 1.2 to 1;.4. A Bk horizon is present in some pedons: ' The C horizon has a matrix with SY or 2.SY hue, value of 4 to 6, and chroma of 2 to 4. It is loam or clay loam and is slightly alkaline or moderately alkaline. COIV�PEZ`�NG SEItIES: These are the Barr�r, Ber�Ril'le,Brookston,Bunfin�+ille, Clackamas, ;I-iarnel,rameseon, MarenQo, Millarove,l�avan,I�losoni,Rensselaer,and We��land:series. Barry soils fiave less than 27 percent clay in the control section. Berville soils contain more than 6 percent gravel in the control section.Brookston soils are more moistin the soil moisture control section during the 120 days £ollowing the summer solstice and have less montmoriilonite in the Iower part af theseries contral section.Buntingville, Clackmas, and Nosoni sails are drier in the soil moistu:re control section during fhe 120 days following the summer solstice. Hamel soils have A horizons 16 to 27 inches thick and and chroma of 1 or less in the upperB horizons. Jameston soils have very firm till beginning at depths ranging from 18 to 30 inches. Marengo � � soils typically have thicker sola,contain appreciable amounts of sedimentary rock fragments in the silry clay lower B and C horizons,.and are more moist in the soil moisture control section. Millgrove soils have up eo 15 percerit gravel in the upper part and 7 percent or more in the lower part of[he control section and very poorly drained.. Na�!an sofls have than 35 percent more clay -in the lower B and C horizons. Rensselaer soils fiave reaction greater than 6:1 in the upper part of . the controi section,are more moist in the moisture control section and are poorly drained. � Wesdand soils have 7 percent or more grave}in the lower part of fhe control section. GEOGR.�I'HIC SETTING:=The Cordova soils have sIightly concave to.slightly convex slopes on broafl flat ridge tops in rolling moraine areas ar on lower lying areas in ground moraines and till plains. Slope gradients are 0 to 2 percent. Soils formecl znostly in friable,calcareous, Iaamy till of Late Wisconsinan age. However, the upper part of the sola irr some pedons is from modified glacial till or drift. The mean annual temperature is about 45 to 52 degrees F. Mean annual�precipitation is about 26 to 32 inches. : .{ . GEOGIPAPHICALLY ASSOCIATED SOII�S: The main ones are the Dund�s, Lest�r, and�e Sueur soils. These soils formed in materials.si�ilar to thase of the Cordova soils and are ' members of a hydrosequence with the Cordova soils. The well drained Lester soils are on nearby : undulating to hilly slopes. The moderately well to somewhat poorly drained Le Sueur and the somewhat poorly to poorly drained Dundas soils are on nearby higher positions. The poorl.y drained Webster and Hamel soils and the very poorly drained Glencoe soils are a nearby associate in a few places.