If moved to another climate where the stress is removed, stress avoiders can become weeds. Calif. Poppy, Iri, Chrysanthemum, Liquid ambar, Roses. Some plants just like to grow and show. This group includes weeds, exotics and most hybridized garden flowers. They can out compete all their neighbors if there is regular water and applications of fertilizer.
Reproduction is their key weapon.
They are the first to flower and the first to seed. They proliferate if the soil has been altered in some way that disrupts the natural community. They will go to seed and die quickly when conditions do not go their way. Weeds can lead to the collapse of a stable native area. Soil amendments, fertilizer, and water fosters their growth.