Ecoregion-specific normalized difference vegetation index (NDVI) quintiles in all HOLC polygons across the Chicago, Los Angeles, and New York City urban areas. Images (A, C, E) in the left column are assigned HOLC grades. Images (B, D, F) in the right column are 2010 NDVI quintiles, with the deeper shade of blue indicating higher levels of greenness. (A) and (B) corresponds to the New York City metropolitan area. (C) and (D) corresponds to the Los Angeles metropolitan area. (E) and (F) corresponds to the Chicago metropolitan area. Note: HOLC, Home Owners’ Loan Corporation.