The necessity of border rows for corn (Zea mays L.) performance test plots is still open to debate. Differences in heights and maturities among hybrids in a particular test potentially can influence the relative importance of border rows. Typically, it is thought that early-maturing hybrids and hybrids that are shorter in height are at a relative disadvantage compared to later-maturing or taller hybrids if plots do not have border rows. A series of experiments was conducted at three sites in two years (six environments) to evaluate the need for border rows in small-plot corn hybrid tests containing hybrids that differ in maturity and height. The six environments provided average grain yields of 4.8 to 14.2 Mg ha^-1. Four corn hybrids were selected to provide contrasting combinations of maturity and height. Four-row plots, 9 m in length, were planted for each hybrid in a randomized complete block experimental design. The inner two rows of each plot served as the bordered-plot treatment. The outer two rows of the same hybrid functioned as the unbordered-plot treatment in a type of split-plot arrangement. Yields differed between hybrids in each environment, and hybrid ranks differed between environments. The non-significant hybrid*plot-type interaction in all six environments supplied evidence that hybrid yield ranks did not change significantly in response to presence or absence of border rows. Bordered vs. unbordered contrasts for yield of each hybrid were not significant (α = 0.05) in all environments. Standard errors of differences (SED) for yield from unbordered plots either were not different or were significantly smaller than those from bordered plots. This further supported the conclusion that bordered plots are not necessary for accurate estimation of yield ranks in corn hybrid performance tests with a range of hybrid maturities and heights.