A greenhouse whitefly. Photo credit: gbohne/ Wikimedia Commons

The whitefly is kind of cute looking as far as invasive pests go, but they’ve recently been expanding their reach and are presenting a new threat to landscapers, gardeners, and farmers in the United States.




According to a report posted by Agence France-Presse, the Q-biotype whitefly, which was known for mostly keeping to greenhouses and nurseries, was spotted outside in the US for the first time. The University of Florida, which carefully studies the whiteflies in the state, said it was first spotted in the country in around 2004 and has been seen in around 25 states since.

While an invasive species is usually a bad thing in any other case, scientists are particularly worried about this species, which is resistant to pesticides and spreads viruses that can destroy crops.


“The resistance to pesticides—that is what really sets them apart,” Lance Osborne, a professor of etymology at the University of Florida, said according to the report. “The best single treatment we have kills 90-91 percent of them. That is as good as we can do without multiple applications.”

Additionally, modern neonicotinoids—a type of insecticide—known to be effective against the whitefly are harmful to other species, such as bees.

It turned up in April in an affluent neighborhood in Florida’s Palm Beach County, which often have ornate gardens. The most commonly attacked plants tend to be ornamental, such as allamanda, or fruit trees like avocado, mango, and citrus. They’re drawn to the plant’s leaves to feed, but secrete a sticky substance, called honeydew, that allows fungus to grow and stunt plants’ growth. The insects are also known to spread more than 100 viruses that can make fruits and vegetables inedible.

Another thing that makes whiteflies tough to manage is the sheer number of plants they can live on. Whiteflies can live on 600 different kinds of plants, 300 of which are grown in Florida, making it tough to target a specific species. Considering the swampy weather in Florida, which makes it a hotbed for bugs, the issue has become serious locally, with government officials worrying about the economy.


“With our climate, robust international trade and more than 100 million visitors a year, Florida is a hotbed for agricultural pests and diseases,” Florida agriculture commissioner Adam Putnam said in an email to AFP. “The Q-biotype whitefly poses a serious risk to Florida’s $120 billion agriculture industry and the more than two million jobs it supports.”

There are two main types of whitefly: B-biotypes and Q-biotypes. Experts credit the B-biotype for destroying crops in the southern US in the 1980s and 1990s. Both can be devastating for plants, but the Q-biotype is known to be more resistant to pesticides. It’s also possible that they can also develop resistance faster than their cousins, according to the USDA, which makes repeated uses of certain pesticides ineffective.


While Osborne told people not to panic—since experts are working on a program that can fight the whitefly and haven’t caused any extreme damage yet—he admits that there is “no magic bullet” for the whitefly. But the government has been working on the issue since at least 2008, such as with a task force that is developing treatments.

Florida in general has been facing some environmental and ecological recently, including a particularly revolting algae bloom and quickly increasing sea levels, so you can add insecticide-resistant bugs to the list.


Correction: A previous version of this story had a photo was a moth, not a whitefly. The wire service we pulled it from identified it as a whitefly. We regret the error.

[Yahoo via AFP]