Immigrants -- legal and illegal -- now make up 13 percent of the nation's workers, the highest percentage since the 1930s. Most of the nation's 17.7 million immigrant workers toil at jobs that native-born Americans shun.

Experts point out that the U.S. economy could no longer function without immigrant labor and the influx has had a vast impact on the nation as a whole.

• Immigrants have kept wages low in low-skilled jobs -- while providing organized labor with new recruits.

• They have moved from the coasts and border states and settled in such heartland states as Tennessee and Kansas.

• Jobs in poultry plants across the South -- once held almost exclusively by black Americans -- are now dominated by Mexican immigrants and textile plants now run largely on the labor of Hispanic workers.

• Mining companies are considering recruiting miners from the Ukraine for Kentucky coal fields, nurses are being recruited from the Philippines, and public school administrators are finding teachers in Nepal, Hungary and France.

About 700,000 immigrants enter the U.S. legally each year -- supplemented by an additional 300,000 who enter illegally or overstay their visas every year.

Overall, there are an estimated 30 million immigrants in the country -- of which about 8.5 million are here illegally.

Source: Laura Parker, "USA Just Wouldn't Work Without Immigrant Labor," USA Today, July 23, 2001.