Effects of a native parasitic plant on an exotic invader decrease with increasing host age

Infection by parasitic plants has been considered as an effective method for controlling invasive plants because the parasites partially or completely absorb water, nutrients, and carbohydrates from their host plants, suppressing the vitality of the host. In a recent study published in AoB PLANTS, Li et al. verified that younger and smaller Bidens pilosa plants suffer from higher levels of damage and are less likely to recover from infection by the parasitic plant Cuscuta australis than relatively older and larger plants, suggesting that Cuscuta australis is only a viable biocontrol agent for younger Bidens pilosa plants.