Editing Centaurea diffusa (section)

===Human influence on invasion===
One of the first influences humans had on diffuse knapweed was to inadvertently introduce it to North America.

Diffuse knapweed is known to establish more easily and effectively in recently disturbed environments. Disturbed environments generally present low environmental stress because more resources are available than are being used. These available resources often allow the establishment of an invasion in an ecological community. The concentration of diffuse knapweed in such an area is often linked to the level of soil disturbance. Human disturbances often lead to less [[species diversity]] in a community. In turn, less species diversity can lead to unused resources, which allow invasive species to more readily establish. Areas such as fallow land, ditches, rangelands, residential and industrial districts and roadsides are all disturbed habitats where diffuse knapweed frequently establishes. Additionally, the removal of foliage and other ground cover increases the likelihood that seeds will come in contact with the soil and [[germinate]].{{citation needed|date=October 2022}}

The largest impact of humans on diffuse knapweed is efforts in controlling and eradicating its invasive populations. Besides reducing the spread of diffuse knapweed, efforts are also providing selective pressure against the individuals that cannot withstand a certain method of control. Selective pressure, given sufficient time, can cause the [[adaptation]] or [[evolution]] of invasive species such as diffuse knapweed. If an individual diffuse knapweed plant survives control efforts because of a trait it possesses, its progeny will make up a greater portion of the population than the plants that succumbed to the control.