Orange Hawk Weed

4 – Eradication, Control, Or Containment

a. When is eradication possible for this species?

Orange hawkweed is a highly invasive and widespread species in the road connected portions of the state. Widespread species such as this can be difficult to identify when eradication is possible, and when management goals should focus on containment or control. Eradication in this context means complete elimination of the species with a very low chance of reinvasion from surrounding areas without human assistance. Containment means to limit the species spread to particular areas, and control indicates mitigating the species impacts to desired land management objectives while accepting its presence as unavoidable.

Eradication is feasible if there are no surrounding infestations in the general area (e.g. community), and adequate prevention measures can be put in place to prevent re-invasion. Complicating matters for orange hawkweed is the windborne seed and ability to reproduce from a single propagule. Thus, surrounding infestations in the general area may be relatively far away compared to other invasive plant species. When threat of reinvasion is high, but preventing invasion of lands with productive management is the goal (e.g. farmland, wildlife area), containment to adjacent areas (e.g. roadside, trailhead) in order to prevent invasion of productive areas is a viable management goal. Containment involves managing the hawkweed populations to reduce or eliminate seed production that are likely to infest nearby priority areas. Control occurs when hawkweed is already infesting an area and is undermining land management goals. In these situations the immediate priority is to control hawkweed population to levels that will not impact desired production. The amount of hawkweed that can be tolerated in these situations will vary based on desired vegetation, observed impacts, and return of cost on investment in control. For example, if hawkweed is present in a pasture controlling it to the point that available forage is not reduced is adequate. However, if hawkweed is present in a hay field meant for sale to others, hawkweed cannot be tolerated as it is a prohibited noxious weed and thus cannot contaminate commodities.