The efficiency of various Latin Square Design (LSD) relative to Completely Randomised Designs (CRD) and Randomised Complete Block Designs (RCBD) for various sizes and shapes of plots on natural grasslands of Outer Himalayas having steep and very steep slopes (25–35 and 35–50 per cent) were worked out. The relative efficiency (percentage) of 3x3, 4x4, 5x5 and 6x6 LSD for different plbt sizes and shapes were compared with CRD and RCBD when rows are treated as columns (ignoring columns) and when columns are treated as blocks (ignoring rows). The number of units required in CRD and RCBD taking rows as blocks or columns as blocks for obtaining the relative efficiency (RE) equivalent to that of 3x3 to 6x6 LSD were also evaluated. It was found that LSD was more efficient than CRD and RCBD for experimentation in natural grasslands of Outer Himalayas under steep and very steep slopes when plot size considered upto 8 m.
