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Ventenata (Ventenata dubia) is a relatively new invasive annual grass to rangelands in the Pacific Northwest and the Great Basin. Although its spread has been rapid in the last decade, very little is actually known about this new invasive grass and how it will affect rangelands in either region. Some report that V. dubia is competitive enough to replace other invasive annual grasses as well as native perennial species. However, there are no published studies available to support this claim. In this study, we performed a greenhouse experiment to examine if V. dubia has a competitive effect on Bromus tectorum, Taeniatherum caput-medusae, or Pseudoroegnaria spicata. Given that both B. tectorum and T. caput-medusae are also winter annuals, we expected that any competitive effects from V. dubia would be greater between annuals than for the native perennial grass. To test this, we compared the early seedling growth rates, final biomass, and competitive performance index for these species grown alone and in competition with V. dubia. Contrary to our expectations, our results showed that P. spicata grown in competition with V. dubia contained 20% less shoot biomass than when this species was grown alone and that the CPI for V. dubiagrown in competition with P. spicata was greater than for either annual grass. Our results suggest that, at this stage of plant development and when grown in one on one competition, V. dubia has more of a competitive effect on the native grass than other invasive annuals. Even with the rapid increase in this species, its invasion may still be within a lag phase of introduction, a time when control is more possible and less costly. More work needs to be done to understand how V. dubia interacts with other species and with increasing densities to understand how it will affect rangelands.