(msnbc.com) — America’s wealthiest black county is in trouble. Prince George’s County, Md., has gained prominence in recent years as the most affluent county in America with a majority African-American population. Average income in the county is almost double the national average for black families, according to the Census Bureau’s 2009 American Community Survey. But the county, adjacent to the District of Columbia, has been laid low by the recession and the mortgage meltdown and now holds a more dubious distinction: a rising foreclosure rate that ranks as the worst in Maryland. More than half of all housing sales in the county so far this year have been properties in foreclosure, a rate that dwarfs other counties in the state, according to MRIS, which provides listing services for real estate agents. This has caused a domino effect of social, economic and financial problems to ripple throughout Prince George’s communities. Foreclosure sales, which have risen from 34 percent in 2009 to 51 percent so far this year, are just one sign of problems affecting Prince George’s.