LOS ANGELES, April 21 (UPI) -- Los Angeles is at the leading edge of a U.S. demographic trend, with half of its workforce immigrants, many of them unskilled and speaking little English.

As baby boomers retire, the same pattern will emerge across the country, the Los Angeles Times reported Sunday. Demographers estimate that by 2025 most of the growth in the workforce will be from immigrants.

Ernesto Cortes Jr., Southwest regional director of the Industrial Areas Foundation, said Los Angeles is at a crossroads.

"The question is: Are we going to be a 21st century city with shared prosperity, or a Third World city with an elite group on top and the majority at poverty or near poverty wages?" he asked. "Right now we're headed toward becoming a Third World city. But we can change that."

The Migration Policy Institute used U.S. Census data to determine that one-third of immigrants have not graduated from high school and 60 percent do not speak English fluently.

Cortes, with former U.S. Housing and Urban Development Secretary Henry Cisneros and others, is to participate in a conference this week at the University of Southern California on how to train and integrate immigrant workers.