From the dry spell that threatened the Pilgrim's corn crop in 1621 to the devastating droughts on the Great Plains in the 1880s and 1930s, lack of rain has been a periodic plague in America.

"Of the many natural forces that wage war on farmers and ranchers, the most demoralizing is a prolonged drought," President Dwight Eisenhower said during the 1950s drought. "In its grip, the individual farmer is well-nigh helpless."Perhaps the worst instances of drought in American history dried out the Plains both 50 and 100 years ago and hit the Southwest in the 1950s.

Whether the current drought will match the disasters of the past remains to be seen, but a look back shows it is not unique.

Firmly fixed in American memory is the dry time in the 1930s, which coincided with the economic chaos of the Great Depression.

The plight of homeless farmers heading west was recounted in books such as John Steinbeck's "The Grapes of Wrath." The term "Okies," for those who fled Oklahoma's parched farms, became attached to millions of Americans displaced from the land.

In many respects, the era was an echo of the 1880s.

Twenty years of good rainfall ended in 1881, and the dry spell held on until 1887, launching an exodus of farmers from Kansas and Nebraska.

"In God we trusted, in Kansas we busted," was a popular saying of the time, according to weather historian David Ludlum. One writer of that era estimated that half the residents of western Kansas had departed by 1892, and dry summers from 1893-95 didn't ease the misery.

Both of these earlier droughts followed wet periods that had encouraged increased settlement, cultivation of land and overgrazing.

"Each drought period set in motion an emigration that grew into a rout. In both cases the series of rainy years had been mistaken for normal climate, with disastrous results," the Department of Agriculture reported in 1941.

By some accounts, the drought of the 1950s was as bad as those before. And records of lengthy dry spells threatening American crops date back to 1621 and the Pilgrims.

The dry spell that threatened the Pilgrims' crops lasted just 24 days, Ludlum reported in "The American Weather Book." But drought threatened again in 1623, killing the corn crop.

Here is a look at some of the other droughts that have affected the United States:

-The 1950s was a time when dust storms once again swirled across dry land on the Plains. Tree ring studies conducted by the University of Arizona indicate that the 1950s decade was the driest period in the Southwest in 700 years.

-It was the Northeast that suffered from drought in the 1960s. Major cities faced shortages with reservoir levels falling to record lows in the driest period in 160 years.

Forest fires swept large areas, washing cars and watering lawns became illegal, and diners had to ask for water at even the most posh eateries. Wells failed, leaving farmers without water, and the level of the Great Lakes dropped alarmingly.

-Drought was felt at the end of the 1960s and early 1970s in the Southwest and in Florida, raising dust storms in Texas and leading to grass fires even in the Everglades swampland.

-California was the victim of drought in the later 1970s, suffering its driest year on record in 1977. Water rationing was implemented and farmers lost an estimated $2.4 billion.