Spatial variation from soil and related factors o en a ects the outcome of agronomic eld experiments. e randomized complete block (RCB) is the most prevalent design despite ine ciencies that can result in in ated error terms. Experimental designs such as the Latin square (LS) allow for bidirectional blocking and o er the potential to account for spatial variability better. e objectives of this research were to investigate the occurrence of two-way gradients in agronomic eld trials and compare the estimated relative e ciency (ERE) of a LS to a RCB. irty LS trials were evaluated in 10 states during 2013 across the midwestern United States investigating crop yields of corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and sorghum [Sorghum bicolor (L.) Moench]. e results show that 47% of the trials exhibited a two-way gradient, indicating this characteristic is widespread across a large geographic region. Overall, the ERE was increased in 70% of the trials by using the LS design. A lower ERE occurred in 7% of the trials conducted using a LS. Multiple gradients appear common in agronomic eld plot trials and enough variation existed between the two blocking directions to justify the use of a LS design. Our data indicate the LS o ers a low risk, high reward option of experimental design for controlling spatial heterogeneity and increasing precision. When possible, the LS design should be used in eld experiments where the trial area appears uniform and gradients to block against are not obvious.