The Soils of Elgin County - Agriculture and Agri-Food Canada

Soil DescriptionsThis section contains generalized descriptionsof the soils which occur in the County . Thedescriptions arearranged in alphabetical orderandinclude information on landform and topography,soil moisture characteristics, general soilcharacteristics, soil variability, and land use andmanagement . Guidelines for determining somesoil moisture characteristics were obtained fromthe CânSIS Manual for describing soils in the field(12). Estimates of water holding capacity wereextrapolated from water retention data obtainedfrom detailed sampling of selected soils in theCounty. That data is presented in Voliune 2 of thereportGeneralized soil profile descriptions for mostsoils are provided in Appendix 1 in this volume ofthe report. This information is presented in tableformat, and includes mean values for horizondepths, textures, pH, organic matter and CaC03 .Similar tables, along with more detailedmorphological, physical and chemical descriptionsof typical soil profiles, as well as engineering testdata, are presented in Volume 2 .Land use comments are included in the soildescriptions, and pertain to : 1) the capability ofthe soils for common field crops; 2) the suitabilityof the soils for special crops, and 3) the suitabilityof the soils for conservation tillage practices.Common field crops include grain or silagecorn, wheat, oats, barley, and forage crops . Theyare the crops for which the Canada LandInventory soil capability ratings for agricultureapply (17) . The capability ratings which apply tothe soils are given in the descriptions, and also inTable 4 of the reportSpecial crops include vegetable, fruit, and nutcrops. They also include less commonly grownfield crops such as spring canola and winterrapeseed. The types of special crops, and theapplicable soil suitability ratings for them, aregiven in Tables 6, 7, and 8. Examples of somespecial crops identified in the tables includepotatoes, cucumbers, peppers, strawberries,tobacco, and winter rapeseed. Comments on thesuitability of the soils for special crops areincluded in the soil descriptions, and are usuallygeneral comments related to the full range ofspecial crops which are identified in the tables .The suitability of the soils for specific crops,therefore, must be determined from the tables .General comments in the soil descriptions onthe suitability of the soils for conservation tillagepractices are based on personal knowledge of thesoils and conservation tillage practices, as well asinformation provided in the Ontario Ministry ofAgriculture and Food factsheet titled " Suitabilityof Conservation Tillage Systems to Ontario SoilTypes" (18) .Four soil textural groups are defined in thefactsheet for surface materials . Although slightmodifications were necessary, the textural groupshave been incorporated into the soil descriptionsin order to better relate potential conservationtillage practices to the soils in the County. Thedefinitions of the textural groups are as follows :1) Coarse - soil materials which contain 52% ~ormore sand, and less than 20% clay. Commonsoil textures associated with this group includesand, loamy sand, and sandy loam.2) Medium - soil materials which contain lessthan 52% sand, and less than 27% clay .Common soil textures associated with thisgroup include loam and silt loam.3) Fine - soil materials which contain either:20 to 40% clay if the sand content is more than45%; or 27 to 40 % clay if the sand content isless than 45%. Common textures associatedwith this group include silty clay loam andclay loam.4) Very Fine - soil materials which contain morethan 40% clay . Common soil texturesassociated with this group include silty clay,clay, and heavy clay.The textural triangle shown in Figure 11provides information on the soil texture classeswhich are included in the four textural groups.24