It is a problem in grasslands on coarse soils with 46 to 51 cm of annual precipitation, which includes the Cypress Hills, North Battleford, and Peace River regions. Cattle avoid it in pastures so forage within infestations is unused. Yellow toadflax is an overwintering host for the cucumber mosaic virus and the broad bean wilt virus and it is a primary noxious species under the Canada Seed Act 1986 and listed by Nova Scotia, Manitoba, Saskatchewan, Alberta, and British Columbia. Yellow toadflax is resistant to most herbicides and its presence on crop land precludes zero or minimum till and shortens the rotation of perennial crops. Mowing reduces seed production without achieving control.
Yellow toadflax is a difficult target for biocontrol.
Much of the problem is on cultivated land, where cropping practices disrupt insect life cycles and cultivation discourages mycorrhizal fungi 7 which probably makes the roots less nutritious for insects. Seed production is prodigious, continues longer into the fall than most seed-feeding insects and continuous summer growth enables the plant to recover rapidly from defoliation. Six of these are established in Canada and one, Gymnetron linariae , has not survived. The prospects of finding additional species in Western Europe with a suitably narrow host range is poor, but the SW Asian diversity center has not been surveyed. The weevils, Gymnetron antirrhini and G. netum , form galls in the seed capsules.