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Current policy recommends that rangelands be rested from grazing for two growing seasons following fire to allow for proper recovery, despite the lack of empirical literature supporting this recommendation. We aim to determine if grazing the first growing season following a spring wildfire alters later productivity and species composition of northern mixed grass prairie. Following the April 2013 Pautre wildfire in northwestern South Dakota, exclosures were erected in three burned pastures to simulate two growing seasons of rest. Grazing exclosures were paired with sites grazed both the first and second growing seasons following the fire and replicated across loamy and sandy ecological sites. Prior to grazing the second growing season, five 2 m� cages were placed at each grazed site to assess first-year grazing effects. Following the second growing season, productivity and species composition were determined for exclosures and cages. Current-year productivity differed between ecological sites as loamy sites were more productive (Loamy= 2764 kg/ha, Sandy = 2356 kg/ha; P=0.0271), but was similar between grazing treatments (Rested= 2556 kg/ha, Grazed= 2564 kg/ha; P=0.9550). Ecological site strongly determined species composition. Loamy sites consistently contained more Pascopyrum smithii, Bouteloua gracilis and Carex duriuscula than sandy sites (30 v 0%, 18 v 8%, 4 v 1%; P= 0.0004, 0.0457 and 0.0382 respectively). The effects of grazing exclusion manifested in only Hesperostipa comata and Agropyron cristatum. H. comata was more prevalent on rested sites (22 v 15%, P=0.0096). A. cristatum experienced a grazing treatment by ecological site interaction as it was reduced by grazing on loamy sites, but was not affected on sandy sites (P=0.0226). Our results do not support the notion that a two growing season rest period following fire is necessary and indicate that grazing may resume the first growing season following spring wildfire with no negative effects.