Quercitron Oak and Its Relation to Soils

Quercitron oak (Quercus velutina Lam.) is sparsely distributed in Iowa, being reported by Pammel in only nine counties. The only patch known in Story County is this area some three miles northeast of Ames, which is a narrow strip about three miles long. Here its distribution conforms very definitely with the occurrence of an area of Carrington fine sandy loam, which soil was apparently deposited by glacial streams on common glacial till of boulder clay. The type lacks uniformity in depth, much of it showing less than three feet of sand. Where the sub-soil corresponds, it is light grayish-brown to yellowish sand. The oak has failed to spread to adjacent upland clay loam (Carrington) and terrace silt loam (Wabash), thus showing utter dependence on the fine sandy loam