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Large and intense droughts raise concerns about appropriate management responses, but equally intense droughts may occur at smaller spatial scales, even when large droughts don't occur. Typical rangeland management units are 5-15 km2, therefore detecting small-scale drought is critical. We compare the spatial scale of drought between summer and winter seasons, and whether those patterns changed after the recent dry period began in 1996. We use two measures of dryness, Standardized Precipitation Index (SPI) and Standardized Precipitation-Evapotranspiration (SPEI) because the later includes temperature. We define drought as the lowest 20th percentile (driest 15 y) in the 73 y record (1940-2012); summer is Jun-Sep and winter is Oct-May; and the data represent the 225 km2 Santa Rita Experimental Range in southern Arizona, using monthly records from 22 gauges and temperature from PRISM. SPI and SPEI were estimated separately for one hundred 2.25 km2 cells using an interpolated precipitation surface. Large-scale drought frequencies were more common since 1996 (41-65% of years) except for summer SPI which was less common. In both seasons, management unit-sized patches were very common before the large-scale SRER reached a drought condition. Since 1996, there was an increase in large patches in winter and increase in management unit-sized (5-15 km2) patches in summer. Drought patch size distribution is less uniform using SPI than SPEI in winter, but in summer they are very similar. Drought was most patchy in summer (SPI=SPEI), and least patchy in winter (SPI).