Grazing operations are interested in grasses that will promote livestock performance and thrive under a management intensive grazing system. Our objective was to evaluate pasture productivity and dairy heifer growth when grazing either meadow fescue (MF; variety Hidden Valley) or orchardgrass (OG; variety Haymaster) at the University of Wisconsin Marshfield Agricultural Research Station. Six pastures (1 ha each) were used with 3 blocks (2 pastures/block) and grass treatment randomized within each block. Pre-pubescent heifers (n = 24) were blocked by weight (8 heifers per weight block; low, medium, high) and randomly assigned to graze MF or OG in each block with 4 heifers per pasture. Three years of study were completed with different heifers used each year. No supplemental concentrates were provided. Mineral was provided daily to meet mineral and vitamin needs. Body measurements were taken at the start and end of the grazing season. Grazing commenced in late May. Forage height measures were taken with a rising plate meter. Calibration of height measures to estimate forage availability was done by clipping 3 locations in each pasture. Data were analyzed using Proc Mixed (SAS v9.4) as a randomized complete block design with year as a repeated measure. Meadow fescue had lower forage availability (849, 865, and 1423 kg/ha in 2016, 2017, and 2018, respectively) than OG (1022, 891, 1471 kg/ha for 2016, 2017, and 2018, respectively). Average daily gains were similar (P = 0.14) for heifers grazing MF (0.78 kg/d) and OG (0.74 kg/d). Hip height gains and body condition change were also similar between MF and OG (P > 0.28).Both Based on these results, both grass species are suitable forage sources for grazing young heifers.