Growing Potatoes:

The Potato Beetle


Potato Beetle Gallery

Charles Riley published the first book about the potato beetle in 1876.
This is London edition published a year later.


Watch fob of a potato with a beetle, USA, circa, 1900's.

German potato bug poster, 1950's.

Cartoon showing a grateful German king honoring
the potato beetle with the iron cross for having
destroyed enemy (French) potato crops
during the first world war.



German booklet, late 1930's instructing the public
especially school children how to battle the potato beetle.

Cartoon battle between attaching beetles and fleeing potatoes.
This illustration was published in the booklet above to instruct
children about the pest.


German schoolchildren being taught about the potato beetle.
Note the poster on the wall.

German children walking the potato fields searching for beetles.
Note the boy second from left wearing the brown shirt of HitlerYouth.


Potato beetles were handpicked off the foliage and killed in collecting bottles.


Everywhere Germans were reminded of the importance of the potato beetle
(kartoffelkafer), here the message is delivered in a postage cancellation.


The potato beetle is a decorative depicted on postage stamps.


A Social History of the Potato Beetle



Advertising trade card from Salem, Massachusetts, circa 1890's, featuring the potato beetle.

"Man is bigger than the potato bug and he will master it."

---Horace Greeley

What Horace, who is mastering whom here? The potato bug remains among us, subdued but hardly mastered. From the bug’s point of view, what a success story! Shadowy beginnings in the American plains (though increasingly researchers are discovering the bug may have originated in Mexico and Central America) featured rapid triumphant mass migrations eastward from the 1800s to the present day. A half-inch long yellow and black striped traveler is now touring the outer reaches of Siberia.

Unlike its colleague in devastation, the desert locust, the Colorado beetle or Leptinotarsa decemlineata Say changes its habitat. As noted by a 1975 document put out by the World Meteorological Organization in Geneva, the beetle is "constantly moving into fresh areas, crossing international borders, and therefore to some extent catching the authorities off guard." The bug also adapts, as all good insects do. Its ability to survive what the chemical industry throws at it, over time, is remarkable.

From the beginning the beetle has elicited respect, even affection, from its chroniclers. The earliest book we know about is C.V. Riley's Potato Pests written in 1876.

Colorado potato beetle or potato bug was first described under the scientific name of Doryphora decemlineata, in the year 1824 by Thomas Say, who was a naturalist exploring the Rocky Mountains.

The original food plan of the beetle was subsequently found to be the sand bur, a species of wild potato peculiar to the region.

By 1859, Riley reports, the beetle had switched its gustatory allegiance to the cultivated potato and pioneers of the breed had migrated to a point "100 miles west of Omaha, Nebraska." Riley also notes that the first press coverage received by the bugs was a letter printed in the Prairie Farmer for August 29, 1861. A Mr. J. Egerton of Grairty, Iowa wrote: "They made their appearance upon the vines as they were up, devouring them as fast as they grew."

An 1865 observer estimated the bugs progress eastward at 50 mph. In the summer of 1871 the Detroit River was reported "literally swarming with the beetles." And they were crossing Lake Erie in droves on anything that floated. The New York Times described swarms of beetles covering railroad tracks. Wheels slipped on the bug-strewn tracks as if oil.

In the 1870s the presence of the beetle was so much a part of the Eastern scene that for a brief time ladies black and yellow-striped evening capes were the fashion. And a joke of the period had potato beetles studying mailing lists of seed companies to find out who had ordered seed potatoes.

Even music claimed the potato bug. The Italian mandolin, a five stringed instrument with a striped round back or sounding board was known in some circles as the "’tater bug mandolin," or "Taterbug" for short.

Tatar bug troubadours traveled the back roads of the South, singing and strumming on their mandolins for a night's lodging or a good meal. A 1969 tune by Mike Millius and Don Thomas immortalized the "Tater bug mandolin man," who was evidently as dangerous to women as the beetle was to the spud crop. As one line in the song goes, "Now they’re sparin’ no expense just to protect our land, but they've yet to invent the defense against the Tater bug mandolin man."

Meanwhile the actual insects were bedding down for the winter. Everywhere. "On dry or wet or sandy soils, one clay or rich and alluvium, on plane, hillside or mountain, in the open, and even in the forest," according to a 1906 treatise.

The adult beetles, then as now, winter over in the ground. With the arrival of spring the bugs emerge and walk or fly " (short flights only) to the nearest potato field and begin to eat. And then to mate soon thereafter. The eggs are laid on the underside of the potato plant’s leaves. Larvae hatch from the eggs and begin their intake of food until they mature, fall to the ground and bury themselves in the soil. Ultimately, an adult beetle emerges in the ground in the cycle is complete.

A small paragraph in the second issue of the Potato Magazine, July, 1918 marveled at the potato bugs fecundity. "The potato beetle is more than a match for the white Leghorn hen when it comes to egg laying. One female can produce 1800s in 1900 eggs. The progeny of two or three broods would form a veritable army of bugs. Moral: spray early and often."

And spray we did, with Paris Green, a copper compound, with Bordeaux mixture, a lead-filled poison, with DDT, a killer chemical discovered by the Swiss in the 1940s almost by accident. They'd been looking for a better moth-proofing compound "(DDT was first successfully tested on potato beetle infested Swiss potato fields."

DTT held sway for many years but the potato beetle developed resistance to it, as it had done to its predecessors. Then follow the synthetic pesticides. Now research indicates that the resilient bugs may well contain an enzyme system which can detoxify certain chemicals. Meanwhile, the toxins were leaching into groundwater systems.

To those who tried to stay one hop ahead of our striped friends were thinking natural predators.

Before there were sprays, there were birds, who ate the bugs right off the plant. The rose breasted grosbeak, the cuckoo, the bobwhite, assorted thrushes, the scarlet tanager, the cardinal and the English sparrow. Of course these birds could not always be counted on to stay on the job regularly, so many farmers let the hens loose in the potato fields. The free range chickens paid their way with more than just eggs.

Birds and farmyard fowl could not keep up with the pest on large farms. Children and other dexterous workers picked the bugs off by hand or beat them off the leaves with sticks often dropping the beetles into tins of kerosene. German friends of ours report that as children during World War II they were let out of school to pick bugs. In 1950 a Spanish leaflet urged children to spend their holidays in the patriotic task of debugging potatoes. An American poem the period tells the child's view of all this:

"There must be some special reason for weeds
And potato bugs and such,
Maybe God made them so that boys,
Wouldn’t mind going back to school too much."

Bugs, wasps and flies are the latest predators to be wooed by researchers. These tiny creatures have been discovered living in Mexico in close proximity with the potato beetle. They may be used with a new kind of chemical which messes up the potato bugs’ reproductive works.

The Colorado potato beetle, remember, is no parochial pest. It adapts equally well throughout Europe and now is learning to make itself at home in Asia. Only the United Kingdom has kept the doors mostly shut.

The beetle was first spotted on the European continent in 1876 and a year later some intrepid Colorado potato beetles arrived at Liverpool on a boat from Texas. The first major infestation was in 1901, when substantial numbers were found in the Tilbury area. Authorities there burned a large area of potato crop with kerosene. "The ground was subsequently soaked with kerosene and dressed with gas line which was then plowed in." This all from, again, the World Meteorology Organization’s well researched tome, "Meteorology and the Colorado potato beetle." When a lone beetle was found in the same area about 60 years later, "2,000 tons of earth received by hand and thousands of acres were sprayed."

Since 1953 few beetles have dared show their stripes in Britain, so wretchedly have they been welcomed. Walk into any post office in the UK and you used to see the wanted posters, with blazing headline reading, "a destructive foreign pest of potatoes." That's our beetle. "If you find it anywhere we want to know." And so on. You're supposed to escort the beetle to the nearest police station , by the way.

Back in 1937 when there was a "scare" in the UK due to the beetle, Punch magazine was moved to announce: "The destructive Colorado potato beetle may lurk in your vegetable garden. Owners of vegetable garden should keep a sharp lookout for beetles with an American accent." Yanks have been taking the heat on the beetle for years. During the Second World War the Nazis accused the allies of dropping potato beetles from airplanes onto Axis potato fields. In 1950 the same charges surfaced from the East Germans, backed up by the Soviet government. The charges, laughable though they seem, underscore the value of the potato and the still formidable task of holding the ever adaptable Colorado potato beetle at bay.

"Take care of your little potatoes, boys, all your tiny spuds,
for the Colorado beetle’s come to collar the jolly lot."
---Anonymous, 19th-century

"The potato bugs eat all of the early potatoes, and then they sit on the fence waiting for the second crop to come in."
From London Wit, circa 1901.

Did you know? That the French called German soldiers in World War I "doryphore" (potato beetle) because they wore striped helmets. During World War II the nickname persisted because the Germans made off with the civilian potato crop.




A Natural History of the Potato Beetle


Spanish pamphlet on the life cycle of the beetle, 1937.


The Colorado potato beetle (Leptinotarsa decemlineata, also known as the Colorado beetle, ten-striped spearman, the ten-lined potato beetle) is an important pest of potato crops. It is approximately 10 mm (0.4 inches) long, with a bright yellow/orange body and bold brown stripes across the length of its elytra, and it can easily be confused with its close cousin the false potato beetle. The beetle was described in 1824 by Thomas Say from specimens collected in the Rocky Mountains on buffalo-bur, Solanum rostratum.

The origin of the beetle is somewhat unclear, but it seems to be that Colorado and Mexico are a part of its native distribution in the south-western part of North-America.

Life cycle
The female beetle can lay up to 800 eggs at a time, and up to three times per year. The eggs are usually deposited on the leaves of potato plants and other related plants in the genus Solanum. After 4-15 days, they hatch into reddish-brown larvae with humped backs and two rows of dark brown spots on either side, which feed on the leaves. Larvae drop to the soil and burrow to a depth of several inches, where they emerge in the spring as adults after two weeks of pupation. They then return to their host plant to mate and feed.

As a crop pest
The Colorado beetle is a serious crop pest of potatoes. Insecticides are often used unsuccessfully against Leptinotarsa because of the beetle's resistance to toxins and ability to rapidly develop immunity to them. In the United Kingdom, where the Colorado beetle is a rare visitor on imported farm produce, it is a notifiable pest: any found must be reported to DEFRA.

World-wide migration

The potato beetle is an example of one of the most successful animal migrations is history. In less than 100 years it has spanned the globe.