What factor necessitates vigilant monitoring for several growing seasons after apparently successful chemical treatment?
Answer
Saplings can emerge from missed root fragments or dispersed seeds
Persistence is required because regrowth can occur from root fragments that were missed during treatment or from the hundreds of thousands of seeds that a single mature tree can disperse annually.

Related Questions
What specific biological mechanism allows tree-of-heaven to quickly outcompete native flora?What is the primary challenge encountered when only cutting down a mature tree-of-heaven specimen?What is the primary goal achieved by using the basal scoring mechanical tactic?Why are systemic herbicide treatments most effective when applied in late summer or early fall?What is required for a successful Cut-Stump Treatment application?What specific carrier is mixed with herbicides for use in Basal Bark Treatment?What is the consequence of treating tree-of-heaven during the spring or early summer growing season?What factor necessitates vigilant monitoring for several growing seasons after apparently successful chemical treatment?In certain regions like Virginia, the promotion of tree-of-heaven removal is tied to managing which associated invasive species?Which control method listed in the table presents the highest risk of failure due to long-term regrowth if the treatment is not maintained?What must be avoided when considering Basal Bark Treatment for herbicide application?