You can't get either consumption curtailment or population growth reduction without serious tyrannical governmental controls. (dotearth.blogs.nytimes.com)
With native dodder, the greatest growth reduction occurs when the parasite attaches to seedlings; the infestation usually doesn't kill established host plants, but when multiple attachments are made to the same host plant, death can occur. (ipm.ucanr.edu)
In fact, when Tranel and his colleagues tested the effectiveness of the PPO inhibitor fomesafen on an Arkansas population of Palmer amaranth, they found that each successive generation had a higher frequency of the mutation and required more and more PPO to be applied to achieve a 50 percent growth reduction. (sciencedaily.com)