Besides the advantages that diffuse knapweed gains from the ERH and allelopathy, it also possesses several characteristically invasive traits. One factor leading to the superior resource competition of diffuse knapweed is its ability to exist in drought conditions. This advantage allows diffuse knapweed to devote its resources to competition while its neighbors are conserving resources to survive. The high number of seeds produced by diffuse knapweed is also a common trait of invasive plants. A higher density of knapweed will not only increase the concentration of allelopathic chemicals in the soil but will also restrict the nutrients available to native plants. Unfortunately, very little research has been conducted to determine the relative competitive ability between diffuse knapweed and its novel competitors. However, tests conducted on the effect of diffuse knapweed on North American grasses in the absence on allelopathic chemicals demonstrated that the fitness of these grasses declined in the presence of diffuse knapweed. Regrettably, we cannot decide if diffuse knapweed is, for general purposes, a better competitor from this data alone. Comparisons of the deleterious effects between these and other pairs of competitors to arrive at a conclusion.