This can be the case if the weed is extremely difficult to control, if the controls are expensive, and if the weed growth is so dense that it ruins the appearance of the property, lowering the value of your land.
Leafy spurge is a weed that meets all three criteria.
In addition, it crowds out desirable plants such as native grasses and wildflowers. In fact, it can crowd out all other vegetation, resulting in stands of pure leafy spurge. Because leafy spurge is officially designated a Noxious Weed, landowners are legally responsible for its control. The weed is usually found on rangeland, but as more real estate in Montana is sold in parcels one to several acres in size, it is becoming a problem for homeowners as well as for range managers. It grows in a variety of habitats, including open hillsides, valleys, gullies, and along stream and ditch banks.