Silicate weathering is known to bind carbon. This study assesses associations between mineral soil humus content (1960-70) [Hum(us).min(.60’s)] (indicator of soil organic carbon – SOC), groundwater silicon [Si.gw], mineral (“.min”) soil parameters from 1966-70 (“68”) and 1986-90 (“88”): pH, (Ca+Mg+K), proportion of clays in fine mineral soils [Prp.(clays/fims], temperature [Temp] from 1961-90 (“(61-90)”) and 1981-2010 (“(81-10)”) by Rural Centers (RC) (N = 18).