a. When is eradication possible for this species?
Bird vetch is a widespread species in the road connected portions of the state, and is known to infest areas off the main road system. Widespread species such as this can be difficult to determine 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 immediate surrounding infestations, and adequate prevention measures can be put in place to prevent reinvasion. When threat of reinvasion is high, but preventing invasion of the land with productive management is the goal (e.g. farmland, wildlife area), then containment to adjacent areas (e.g. roadside, trailhead) in order to prevent invasion of the productive areas is a good management goal. Containment involves managing the bird vetch populations to reduce or eliminate seed production that are likely to infest nearby priority areas. Control occurs when bird vetch is already infesting an area and is undermining land management goals. In these situations the immediate priority is to control bird vetch population to levels that will not impact desired production. The amount of bird vetch that can be tolerated in these situations will vary based on desired vegetation, observed impacts, and return of cost on investment in control.