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Invasions of non-native plants can cause both environmental and economic damage to a region, including increased wildfires, reduced forage for livestock, degraded wildlife habitat and changes in watershed function.�Ventenata dubia�is a relatively new invasive annual grass to the Intermountain West that has spread rapidly across seven western states (CA, OR, ID, WY, WA, UT, MT). There are many ways that plants from other parts of the world are able to move into a new environment and become the dominant plant.� One of these invasion tactics, called �soil conditioning�, involves the ability of some plants to alter the soil in a way that promotes its own growth while inhibiting growth from competing plants.� Plants can do this in several different ways including altering nutrient levels, changing the microbial community in the soil, or by secreting poisons that affect other plants. The objective in this study was to examine if ventenata is using soil conditioning (altering soils in a way that benefits itself while inhibiting other vegetation) as a mechanism to assist in its invasion. To test this, we compared the final biomass of the native grass bluebunch wheatgrass (Pseudoroegnaria spicata) to the final biomass of ventenata grown in a greenhouse in pots of field-collected soils that were in close proximity and either �conditioned� or �non-conditioned� by ventenata in the same soil type from two different sites. Our results were not consistent across sites, suggesting that either this species is not using soil conditioning to its advantage, has not been on site long enough in both locations to affect changes in soils, or that other soil physical and chemical characteristics of the soil are responsible for the different responses.