Tahlequah Daily Press

Get the scoop!

March 3, 2014

Polar vortex may prove to be a powerful pesticide

— This winter is a real killer.

The deep freeze, with arctic blasts from the polar vortex, has put invasive insects on ice in dozens of states. That includes the emerald ash borer, a pretty bug that does ugly things to ecosystems it invades.

Up to 80 percent of the ash borers died when January temperatures dipped below minus 20 degrees Fahrenheit in St. Paul, Minn., according to an estimate by U.S. Forest Service biologists, who have been conducting studies on the impact of cold weather on the bugs for the past three years.

Their estimates were affirmed when state researchers found that nearly 70 percent of ash borers collected from infected trees in the Twin Cities area last month were frozen stiff - a good thing for ash trees that adorn communities and provide smooth, durable wood used for flooring, bowling alleys, church pews, baseball bats and electric guitars.

Across the country, other destructive pests are dropping dead, including the hemlock woolly adelgid, which preys on Christmas trees in the Appalachian Mountains; the kernel-munching corn earworm, found in nearly every state; the citrus-destroying cottony cushion scale that migrated to Maryland from Florida; and the gypsy moth, which chomps on 80 species of trees and is spreading from the Northeast to the Midwest.

The bugs found their way to the United States from all over the world and thrived in the relatively warm winters of recent years. At least two of the pests mounted great migrations from the Deep South to Virginia and Maryland.

For now, at least, the freeze has stopped them in their tracks. Researchers in the Appalachians of West Virginia and Maryland found hemlock adelgids whose little, straw-like mouths were stuck to the pine needles from which they suck nectar.

"If you poke them with a stick, they'll normally move their little microscopic legs," said Patrick Tobin, a research entomologist for the Forest Service in Morgantown, W.Va. But not this winter.

Based on surveillance, researchers believe more than 95 percent of hemlock adelgids were killed in the northern Appalachians and at least 70 percent died in their southernmost range, Georgia.

At first blush, this appears to be great news, Tobin said. Important trees, including ash, birch and oak, and such vital crops as soybeans, corn and oranges will probably get a break from millions of gnawing mouths.

But invasive bugs are a breed apart. Built to last, they almost never experience extinction.

Female adelgids and cottony cushion scales, for example, are asexual creatures that produce nymphs without copulation. Three generations or more will spring to life between March and October.

As for emerald ash borers, that Minnesota deep freeze affected only a limited number. Chicago also has ash borers, but temperatures there fell only to 17 degrees below zero and likely didn't faze the insects. Minus 20 is the point at which they start to die.

"This problem is not going away," said Rob Venette, a Forest Service research biologist who studied the ash borer.

Winter's blow to the pests is more like a reprieve, said Mike Raupp, a professor of entomology at the University of Maryland, "a little correction" that thinned their ranks and probably will slow them down when warm weather returns.

The cold weather provided a stage for a grand experiment that will help researchers determine if significant numbers of pests can be killed off, making the problems they create more manageable, Raupp said. A decade of study is needed for any definitive conclusions.

Raupp studies the crop-eating brown marmorated stink bug. He said he'd like to be "cautiously optimistic" that winter wiped out huge numbers of them in the mid-Atlantic states, where they have feasted on farm crops for years.

 An experiment conducted by an entomology professor at Virginia Tech gave him hope. Stink bugs placed in foam insulated buckets had a 95 percent death rate when temperatures hovering around zero persisted for days.

The bucket simulated overwintering hideouts in Blacksburg used by stink bugs to protect themselves from the cold.

The conclusion? "There should be significant mortality of [stink bugs] and many other overwinter insects this year," the professor, Thomas Kuhar, told The Washington Post Capital Weather Gang last month.

But Raupp, who called Kuhar "a top-notch researcher," is more guarded. Blacksburg had a few days at 4 degrees below zero, but Maryland did not.

A research entomologist for the Agriculture Department also has low expectations. When researchers for the USDA visited outdoor sites in Maryland where stink bugs spend the winter, they found the same mortality rate - about 50 percent - as in earlier winters.

"Unfortunately, they're doing just fine," said the entomologist, Tracey Leskey.

Stink bugs are from China, where temperatures often plummet. Even if they did die in bunches, they enter "winter with an enormous population," so plenty of survivors rush out in spring to multiply.

A large group of stink bugs cozied up in the warm homes of residents who couldn't seal enough cracks to prevent them from slipping through.

"Every day, I've had a stink bug wandering across my desk," Raupp said. "They're doing fine in my house."

It might seem that frequent snowfall would help kill the bugs, entomologists said, but instead it insulates and protects them.

As if stink bugs weren't bad enough, another invasive bug from Asia has made its way to Maryland. Detected in Georgia in 2009, the soybean-loving kudzu bug has since decamped toward the north.

This winter's polar shock might be that insect's Waterloo. University of Georgia entomologist Wayne Gardner said kudzu bugs are slowed by just a layer of frost. Maryland's temperatures dipped to 5 degrees.

The corn earworm that devastates that crop prefers tropical climates, and typically heads south when temperatures cool. The vortex that hit 49 states with extreme cold and snow offered few safe havens. And gypsy moths were found frozen and flat on their backs near trees they infect.

But the cruel winter apparently had little effect on ticks. In New Hampshire, they continue to weaken adult moose and kill calves. Tick populations are booming because cold weather now arrives in mid-October, too late to kill them in the brush where they wait to hitch a ride on moose until May.

"We've had a higher tick load on moose this fall than we've ever seen, except for one year previously," Kristine Rines, a wildlife biologist and moose project leader for New Hampshire's Fish and Game Department.

To disrupt the tick reproduction cycle, winter would have to arrive "at its regularly scheduled time" in New Hampshire, around late September, said Rines. "We've already seen some . . . calves dying."

 

1
Text Only
Get the scoop!
  • Why a see-through mouse is a big deal for scientists

    A group of Caltech researchers announced in Cell Thursday their success in making an entire organism transparent. Unfortunately, this isn't any kind of "Invisible Man" scenario: The organism in question is a mouse, and the mouse in question is quite dead.

    July 31, 2014

  • Lindley, Tom.jpg Grandstands feel a little empty at NASCAR races

    Two decades after NASCAR started running at Indianapolis Motor Speedway, the crowds have thinned considerably. It's probably no reflection on the sport's massive following, which stretches from coast to coast, but it surely doesn't NASCAR's image help when the cameras pan across all of those empty seats.

    July 31, 2014 1 Photo

  • The virtues of lying

    Two computational scientists set out recently to simulate the effects of lying in a virtual human population. Their results, published in the Proceedings of the Royal Society B, show that lying is essential for the growth of a cohesive social network.

    July 31, 2014

  • lockport-police.jpg Police department turns to Facebook for guidance on use of 'negro'

    What seems to be a data entry mistake by a small town police department in western New York has turned into a social media firestorm centered around the word "negro" and whether it's acceptable to use in modern society.

    July 31, 2014 3 Photos

  • Sunburn isn't the only sign of summer that can leave you itchy and blistered

    You've got a rash. You quickly rule out the usual suspects: You haven't been gardening or hiking or even picnicking, so it's probably not a plant irritant such as poison ivy or wild parsnip; likewise, it's probably not chiggers or ticks carrying Lyme disease; and you haven't been swimming in a pond, which can harbor the parasite that causes swimmer's itch.

    July 30, 2014

  • Rodden, Danny.jpg Sheriff accused of lying about relationship with prostitute

    The sheriff of Clark County, Ind., faces an eight-count federal indictment that accuses him of lying about paying a prostitute for a sex act and giving her a badge so that she could claim a discount rate at a hotel.

    July 30, 2014 1 Photo

  • Sharknado.jpg Sharknado 2 set to attack viewers tonight

    In the face of another "Sharknado" TV movie (the even-more-inane "Sharknado 2: The Second One," premiering Wednesday night on Syfy), there isn't much for a critic to say except to echo what the characters themselves so frequently scream when confronted by a great white shark spinning toward them in a funnel cloud:
    "LOOK OUT!!"

    July 30, 2014 1 Photo

  • Lindley, Tom.jpg Sideshows involving Rice and Dungy stain NFL's image

    Pro football training camps should be all about, well, football. But the talk around the NFL is about Baltimore Ravens running back Ray Rice's two-game suspension, Tony Dungy's indelicate remarks about Michael Sam and Jim Irsay's largesse. What kind of league is Roger Goodell running?

    July 30, 2014 1 Photo

  • 20140729-AMX-GIVHAN292.jpg Spanx stretches into new territory with jeans, but promised magic is elusive

    The Spanx empire of stomach-flattening, thigh-slimming, jiggle-reducing foundation garments has expanded to include what the brand promises is the mother of all body-shaping miracles: Spanx jeans.

    July 30, 2014 1 Photo

  • linda-ronstadt.jpg Obama had crush on First Lady of Rock

    Linda Ronstadt remained composed as she walked up to claim her National Medal of Arts at a White House ceremony Monday afternoon.

    July 30, 2014 1 Photo

  • Medical marijuana opponents' most powerful argument is at odds with a mountain of research

    Opponents of marijuana legalization are rapidly losing the battle for hearts and minds. Simply put, the public understands that however you measure the consequences of marijuana use, the drug is significantly less harmful to users and society than tobacco or alcohol.

    July 30, 2014

  • Can black women have it all?

    In a powerful new essay for the National Journal, my friend Michel Martin makes a compelling case for why we need to continue the having-it-all conversation.

    July 30, 2014

  • 20140727-AMX-GUNS271.jpg Beretta, other gun makers heading to friendlier states

    In moving south and taking 160 jobs with it, Beretta joins several other prominent gunmakers abandoning liberal states that passed tough gun laws after the Newtown shooting.

    July 28, 2014 1 Photo

  • Fast food comes to standstill in China

    The shortage of meat is the result of China's latest food scandal, in which a Shanghai supplier allegedly tackled the problem of expired meat by putting it in new packaging and shipping it to fast-food restaurants around the country

    July 28, 2014

  • Dangerous Darkies Logo.png Redskins not the only nickname to cause a stir

    Daniel Snyder has come under fire for refusing to change the mascot of his NFL team, the Washington Redskins. The Redskins, however, are far from being the only controversial mascot in sports history.  Here is a sampling of athletic teams from all areas of the sports world that were outside the norm.

    July 28, 2014 3 Photos

Poll

Do you think "blue laws" related to Sunday alcohol sales in Oklahoma should be relaxed? Choose the option that most closely reflects your opinion.

Alcoholic drinks should be sold Sundays in restaurants and bars, and liquor stores should be open.
Alcoholic drinks should be sold Sundays in restaurants and bars only; liquor stores should stay closed.
Liquor stores should be open Sundays, but drinks should not be served anywhere on Sundays.
The law should remain as it is now; liquor stores should be closed, and drinks should be served on Sundays according to county option.
No alcohol should be sold or served publicly on Sundays.
Undecided.
     View Results
Tahlequah Daily Press Twitter
Follow us on twitter
AP Video
Netanyahu Vows to Destroy Hamas Tunnels Obama Slams Republicans Over Lawsuit House Leaders Trade Blame for Inaction Malaysian PM: Stop Fighting in Ukraine Cantor Warns of Instability, Terror in Farewell Ravens' Ray Rice: 'I Made a Huge Mistake' Florida Panther Rebound Upsets Ranchers Small Plane Crash in San Diego Parking Lot Busy Franco's Not Afraid of Overexposure Fighting Blocks Access to Ukraine Crash Site Dangerous Bacteria Kills One in Florida Workers Dig for Survivors After India Landslide Texas Scientists Study Ebola Virus Smartphone Powered Paper Plane Debuts at Airshow Southern Accent Reduction Class Cancelled in TN
Stocks