‘Superbug’ Ravaging Crops, Economy in Imperial Valley : Agriculture: Invasion of poinsettia whitefly is expected to lead to shortages of vegetables, higher prices.

A tiny whitefly that feasts on a staggering array of crops has invaded the Imperial Valley, devastating the region’s farm-dependent economy and ensuring that the nation will face severe shortages of fresh produce this winter.

The poinsettia whitefly, dubbed “Superbug” by local farmers awe-struck by its appetite, has wiped out the $22-million fall melon crop and is now attacking the broccoli, carrots, cabbage and cauliflower that distinguish this remote southeastern corner of California as America’s winter salad bowl.

Already, more than 2,500 farm workers have been idled by the infestation, and businesses, from tractor dealers to shoe stores and video rental shops, are suffering from slumping sales, officials say.

If the bug’s unprecedented assault continues as expected, officials predict crop losses will top $200 million by spring--a figure representing more than 20% of Imperial County’s total agricultural output each year.

“This is the worst disaster we’ve ever seen down here,” said county Supervisor Sam Sharp, who fears government services will have to be cut if sales tax revenues continue to slide. “When 90% of your economy is dependent on agriculture and you’re hit by something like this, let me tell you, it’s scary.”

Last month, Imperial County declared a local state of emergency, the first step toward securing aid for beleaguered growers. Neighboring Riverside County--where the insect has claimed $5.3 million worth of crops and now threatens the valuable citrus and table grape industries--followed suit on Tuesday.

Both counties have asked Gov. Pete Wilson to declare a state disaster to help boost funding for research on a solution, something that has so far eluded entomologists. Insecticides have proven futile against the speck-sized pest, and the discovery of an effective natural predator that can survive the valley’s harsh temperatures could take years, scientists say.

Earlier this week, California’s top agricultural official, Henry Voss, toured Imperial County and declared the infestation unprecedented in the state’s farm industry. With him was Assemblyman Rusty Areias (D-Los Banos), chairman of the Assembly Agriculture Committee.

“After witnessing the devastation down there, that whitefly went from 50th on my priority list to first,” Areias said in an interview Friday. “It’s the Imperial Valley that’s hurting today, but it very easily could be the Central Valley tomorrow.”

Indeed, scientists say they know of no reason why the bug could not invade other areas of the state.

“This beast travels with the winds, and when it sees something green, it just drops on down and starts feeding,” said Keith Mayberry, a farm adviser at the University of California agricultural research center near Holtville.

Experts say the poinsettia whitefly is a new strain of the sweet potato whitefly, which has been a problem in cotton and several vegetable crops for decades. The new bug is also very distantly related to the ash whitefly, which ravaged trees and back-yard gardens throughout urban California before parasitic wasps were released, bringing the fly under control.

The insect is believed to be native to Iraq or Pakistan and was first discovered in this country on poinsettia plants in Florida in 1986. Exactly how it arrived there is unclear, but it spread into Texas, Arizona and northern Mexico, and last winter turned up here.

Initially, damage was minor. But this summer, when Imperial County’s hot weather set in, the insect’s numbers began to mushroom, creating huge opaque clouds that stretched across the desert.

“It looked like a blizzard, there were so many of these things swirling in the air,” said Frank Laemmlen, a University of California plant pathologist in Imperial County.

Field workers inhaled so many of the bugs they began to suffer from irritated throats and nasal sores, and eventually were equipped with masks.

Unlike many agricultural pests, which limit their attacks to one or two crops and can be controlled with relative ease, the poinsettia whitefly appears indiscriminate in its tastes. Researchers have so far counted about 500 different plants affected by the bug--and the list grows every day, said Nick Toscano, a UC Riverside entomologist who heads a task force mobilized to study the pest.

It also has decimated Imperial County’s parks and gardens. About the only valley crops the bug has rejected are turf grasses, jojoba and onions. “I’ve been an entomologist for 20 years, and I’ve never seen a pest like this one,” Toscano said.

To the casual observer passing through the valley, things might not look amiss. There are bright green alfalfa fields bordering the roads, and row after row of young cauliflower and broccoli plants.

But pause by a melon field, lean in for a closer look, and the damage is plain to see. The underside of leaves are coated with whiteflies--a layer so thick it disrupts the vital photosynthesis process. The plants are badly stunted and dehydrated, drained of their nutrients by the bugs. The insects excrete a sticky dew that coats the leaves and spawns a black fungus.

If a plant has the strength to produce a crop, the fruit often turns out small, misshapen, stripped of its flavor and discolored by the black fungus--unattractive to consumers.

Bartt Ries works for one of the Imperial Valley’s biggest vegetable growers, and, like other farmers, is depressed, discouraged and terrified of what lies ahead.

“This field here is a total disaster,” Ries said sadly as he knelt beside a 120-acre plot of sickly, drooping cauliflower plants. “See this plant? By this time, the (cauliflower) head should be the size of a golf ball. Look, it’s not even a pinprick.”

The field, Ries said, would be plowed under--a $120,000 investment stolen by the bug.

Imperial County, once little more than a desert, is today one of the richest agricultural zones in the state, a place where the sun always shines and most anything will grow. Close to 90% of the fall and winter produce America eats comes from the Imperial Valley and neighboring irrigated deserts in Riverside County, western Arizona and northern Baja California.

Now, all of these lands have been occupied by the whitefly, and shortages of produce this year are expected to be severe and may begin as early as Thanksgiving. Consequently, prices will rise--perhaps doubling for some vegetables, Mayberry and others said.

With more than 95% of the fall crop destroyed, farmers recently saw the prices on those cantaloupes that the pest spared jump from $3 for a 24-melon box to $20.

The search for a solution has also widened to include the International Institute of Biological Control in London. The institute will aid scientists in their hunt for another bug that might be imported from Pakistan or Iraq, reared and then released in mass numbers to wage war on the whitefly.

Meanwhile, growers and the university farm advisers are trying a wide range of potions on infested crops, searching for a repellent that might salvage some of this year’s vegetables.

El Centro farmer Ben Abatti, who lost his $1-million melon crop and had to lay off 500 harvest workers, said conventional pesticides don’t work: “You spray and chase ‘em off, but two days later they’re back again--and they bring millions more with ‘em.”

Mayberry has sprayed everything from Tabasco sauce to diluted hand lotion on an experimental crop. He even boiled a tea from a ground-up mesquite bush and sprayed it on some cauliflower after hearing that a farmer in Mexico had success with such a treatment. No luck.

In Holtville, population 5,000, the consequences of the infestation are plain to see. The local barber, Walker Deloach, 71, said, “There isn’t a business in town that hasn’t been hurt.”

On the front lines, among farm workers, the news is still grimmer. Even in good years, Imperial County ranks last or nearly last in median family income, and the unemployment rate is almost always the highest among the state’s 58 counties--varying from season to season from about 24% to 30%.

Now, hundreds of jobs are disappearing, and filings for unemployment benefits are rising.

Whitefly: Facts and Figures

Here is a look at the poinsettia strain of the sweet potato whitefly that has ravaged Imperial County agriculture.

Scientific Name: Bemisia tabaci

Family: Aleyrodidae

Size: 2-3 mm

Origin: Entomologists are not certain, but believe that the tropical fly comes from Asia, Africa or the Middle East.

Areas Affected: Portions of Imperial, San Diego, Riverside and San Bernardino counties, as well as some regions in western Arizona.

Crop Damage: $22 million so far, with projections of up to $200 million in damage by spring. The pest has nearly destroyed the entire melon crop and has damaged other crops including broccoli, cotton, alfalfa, grapes, squash, lettuce, tomatoes and citrus fruits.

Compared to other whiteflies: The fly is five times as prolific and pulls five times as much nutrient material from the plants as other whiteflies. The fly is also more tolerant of cold temperatures and more resistant to chemical controls.

SOURCE: Los Angeles County agricultural commissioner’s office and the California Department of Food and Agriculture.

Compiled by Times researcher Michael Meyers