I have always wondered why sandy floodplain soils with evidence of irregularly decreasing carbon are lumped in with Udipsamments (as Aquic and Oxyaquic subgroups in southern Michigan series Abscota and Algansee) , but are not afforded the additional fluventic modifier as one would in other suborders. These soils are fertile and express forests with floodplain tree species (as the fluventic subgroups do) with a rich understory. Other MWD and SPD Udipsamments not in floodplains have a much different, often poorer acidic flora, but even these vary in fertility based on the pH of the groundwater. Other suborders in soil taxonomy are much better classified than sands. But I would argue that sands with their inherently low CEC and AWC means that other properties that affect productivity can have a proportionally larger effect on vegetation that they would in loamier soils. This "gap" in classification makes soil sorts for the purposes of ecological site classification more challenging.
Greg J. Schmidt
Ecological Site Inventory Specialist
Natural Resources Conservation Service
3260 Eagle Park Dr. NE, Suite 104
Grand Rapids, MI 49525
cell - (517) 285-7911
e-mail - greg.schmidt@mi.usda.gov
Ecological Site Descriptions - https://esis.sc.egov.usda.gov/
