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Forbs are important components of ecological systems. In sagebrush steppe there is a general lack of information of long-term forb production dynamics and diversity. In this study we evaluated forb production dynamics for 10 years on 44 high seral Wyoming big sagebrush sites in southeast Oregon for the five main associations identified by the dominant bunchgrass: bluebunch wheatgrass (n=16), Thurber's needlegrass (n=12), Idaho fescue (n=5), needle-and-thread (n=4), and bluebunch-Thurber's needlegrass (n=7). Perennial forb production was greatest on the Idaho fescue association (101 + 10 kg/ha), followed by bluebunch wheatgrass association (84 + 8 kg/ha), bluebunch-Thurber's needlegrass association (78 + 7 kg/ha), Thurber's needlegrass association (46 + 7 kg/ha), and the needle-and-thread association (8 + 2 kg/ha). Perennial forbs represented between 17% and 23% of total herbage production on all but the needle-and-thread association which averaged but 2% of herbage production. Annual forb production was more variable in response to yearly growing conditions (e.g. available soil water, spring temperatures) than perennial forbs. Annual forb production was greatest on the bluebunch-Thurber's needlegrass association (35 + 9 kg/ha), Thurber's needlegrass association (34 + 13 kg/ha), and bluebunch wheatgrass association (31 + 11 kg/ha), and lowest on the needle-and-thread (19 + 7 kg/ha) and Idaho fescue (16 +6 kg/ha) associations. Annual forb production as a percentage of total herbage production ranged between 3% and 9%. Managers should be aware that in the Wyoming big sagebrush complex forbs are more responsive to interannual weather variation and events than disturbances such as fire or mechanical brush control treatments. Studies in Wyoming sagebrush steppe have shown a consistent lack of response by forbs to disturbance. Our study demonstrates the yearly variability in forb production that can be expected and the differences in forb productivity among Wyoming big sagebrush associations.