Studies associated with diaspore self-burial have emphasized the role of awns and substrate surfaces to explain burial differences between species. However, limited research has been conducted to determine the effect of diaspore morphometrics on intraspecific self-burial differences. The aim of this study was to evaluate morphometric and self-burial differences between diaspores of Hesperostipa spartea growing in loam versus sandy soils. Hesperostipa spartea diaspores were collected in three black soil prairies (loam soils) and three sand prairies (sandy soils) in Illinois. Eight morphometric measurements were made from 50 diaspores per site to determine differences between diaspores from these two soil types. Two studies were conducted to determine if self-burial rate and depth of burial differed between diaspores from loam versus sandy soils. Morphometric results showed that sandy soil diaspores were smaller than loam soil diaspores. In addition, regardless of the soil of origin, diaspores were more successful at self-burial in loam soil than in sandy soil due to microtopography. Lastly, diaspores from sandy soil self-buried deeper than diaspores from loam soil regardless of soil substrate. This study demonstrates that there are intraspecific morphometric differences between Hesperostipa spartea diaspores from loam versus sandy soil prairies and that these morphometric differences affect self-burial.