The Palo Alto History Project, Medfly Invasion

The 1981 Medfly Invasion: Pesky Bugs Have State in a Panic

Name a bug smaller than a fingernail that it takes the Governor of California, the National Guard and 80
million dollars to kill. If you said, “The Mediterranean fruit fly” you were probably living in or near Palo Alto
in 1981. In that year, the insect more commonly known as the “medfly” nearly crippled California’s
agricultural industry, wrecked Jerry Brown’s Senate chances and led to a media frenzy that convinced many
in Palo Alto that their homes would soon be sprayed from above with toxic DDT.

California’s medfly morass began on June 5th, 1980 when two medflies were found in a trap in San Jose.
Medflies (not native to the U.S.) are among the peskiest of all Earth’s bugs. By laying their eggs under the
skin of a wide variety of popular fruits, medfly larvae are born inside the fruit, become maggots and destroy
it. Agriculturalists were quick to point out that a medfly outbreak was capable of completely ravaging the
state’s 14 billion dollar agricultural industry and the California economy as a whole. As the medfly began to
be found in increasingly wide circles, California decided to wage war on the intruding insect.

They began with the implementation of the so-called “Sterile Insect Technique.” Since female medflies only
mate once, local governments flooded the Bay Area with some 1.3 billion sterile males. 2,000 workers also
went door-to-door stripping trees of fruit and 62,000 backyards were sprayed an average of 6 times each.
It even became a crime not to strip your fruit trees, punishable by a $500 fine and up to 6 months in jail.
Even the National Guard was called in to help oversee the process. By June 1981, it seemed that the medfly
battle had been won.

But suddenly, the medfly was back with abandon. Although at first it seemed that the bug had inexplicably
acquired some sort of supernatural strength, it turned out that the medfly’s comeback was quite explainable.
Someone in Lima, Peru had messed up big time. Mistakenly, a canister of fertile medfly males had made it
down the assembly line and into California, shipped directly to Palo Alto. As the Valley’s apricots began to
ripen, in came 50,000 horny flies and soon Palo Alto and surrounding towns were flooded with medflies.

In Sacramento, Governor Jerry Brown hesitated. A liberal environmentalist with many supporters in Silicon
Valley, Brown was not keen on spraying chemicals on the base of his political support. Rather than order
aerial spraying, he proposed a new massive ground attack. State Republicans hit the roof. An emergency
session of the Legislature was called, Brown’s poll numbers were in free-fall and there was even some talk
of impeachment.

And the rest of the country began to see there was something amiss in the Golden State. Florida, Texas,
Georgia and even Japan imposed quarantines on California crops, not wishing to acquire their own medfly
populations. And on July 10th, the Reagan administration (no friend of the Democratic governor of the
nation’s largest state) forced Brown’s hand. The U.S. Department of Agriculture announced that unless
aerial spraying began immediately, all California agriculture wound be quarantined. With no cards left to
play, the Governor gave in and ordered the spraying to begin July 14th at midnight in Palo Alto. Malathion,
a commonly used insecticide mixed with a sweet, sticky bait would be let loose from helicopters over the
homes of Palo Alto, Los Altos, and Mountain View.

The media and public outcry was deafening. For several days, nearly the entire front section of the San Jose
Mercury News and San Francisco Chronicle was devoted to stories about the aerial spraying. The Red
Cross set up shelters for residents who wished to escape the line of fire, some doctors came out and said the
elderly and pregnant women were in danger, and Palo Alto, Los Altos, and Sunnyvale sought a restraining
order on the spraying. Some environmentalists even promised to shoot down the helicopters if they tried to
unleash Malathion on local homes.

Over the next few days, the California Department of Health Services rallied itself and flooded the airwaves
with experts assuring the public that the chemical was harmless in small doses---that Malathion was no
worse than bug spray used around the house. They set up a hotline (it received 8,000 calls the first week),
convened a Medfly Health Advisory Committee, and planned studies of the effects of the spraying. Within
24 hours, the news media began to report the expert take on Malathion and the fervor began to die down.
The California Supreme Court turned down the injunction request and the spraying went forward as
ordered.

Two dozen protesters came out in Palo Alto---one sporting a sign saying, “Welcome to Palo Alto, the
Cancer Research Laboratory”---but they had difficulty even located the night helicopters. Although a few
dozen people showed up at the Red Cross the first night, by the end of the week, the shelters were empty
and were closed. No one came forth with any significant ill health due to the spraying.

Over the next few weeks, the outcry faded and eventually the medfly was eradicated. There are still
websites that decry Malathion’s dangerous effects, but most doctors and scientists feel that there is no long-
term danger from spraying.

Although, the medflies never reached the San Jouquin Valley and its valuable farm products, the medfly
scare was enough in itself. The statistics are overwhelming. 2 million households received literature about
how to deal with the medfly, 5 millions cars were inspected for fruit, 100,000 pieces of fruit were
confiscated from them, 4,000 square miles were quarantined and 1,300 square miles sprayed. Prices of
California fruit took a nosedive nationwide costing farmers millions and Jerry Brown went down to defeat in
the California senate race---in part because his perceived vacillation on medfly issue. What a lot of harm a
little bug can do.

-Matt Bowling

The Palo Alto History Project

The 1981 Medfly Invasion

Buttons were handed out as
part of the Medfly PR
campaign

The blue-eyed culprit himself

Palo Alto Home Page

P olitical Issues

A photo and portrait of
Governor Jerry Brown during
the Medfly years.

Historical Events

An old newspaper photo of
Jerry Brown visiting a Los
Altos family home that was in
the "spray zone." The
publicity photo did not help
him avoid defeat in the 1982
senate race against Pete Wilson.

Despite the assurances
of most health officials,
there is still a segment
of the population very
concerned about aerial
Malathion spraying.