From merely annoying to downright destructive, non-native, invasive plant species can wreak havoc on a landscape. As they colonize habitats, invasive species exclude native plants and animals, thereby decreasing native biodiversity. A new study from the University of Illinois has found yet another reason to stop the advance of invasive plants while encouraging the growth of natives.
Researchers discovered that some invasive, non-native plants actually increase the number of adult Culex pipiens mosquitos, which can transmit West Nile virus to humans, domestic animals, birds and other wildlife. They also report, however, that one native plant appeared to have the opposite effect. The two species whose leaves produced the highest quantity of adult mosquitoes when placed in standing water were Amur honeysuckle (Lonicera maackii) and autumn olive (Elaeagnus umbellata).
“These are some of the most widespread invasive exotics in North America,” University of Illinois entomology professor Brian Allan, one of the study’s lead researchers, told Phys.org. “Plants like honeysuckle are having very significant ecological impacts, displacing a lot of native species. And now we’re seeing that some of them also enhance the transmission of a dangerous disease.”
One of the promising findings of the study was that a native blackberry (Rubus allegheniensis), although attractive to the mosquitoes, did not sustain them.
“Blackberry was a really poor habitat,” Allan said. “It took the larvae a long time to develop and the adult mosquitoes that eventually emerged were small. What’s exciting about this is that it suggests that blackberry functions as a kind of ecological trap, enticing mosquitoes to lay their eggs in a place where the larvae are unlikely to survive.” This finding could lead to new, biological methods of controlling Culex pipiens mosquitoes, he said.