 During the post–World War II economic expansion, many persons from rural and urban backgrounds moved to single-family detached homes with lawns in the suburbs or in horizontally developed cities.Pride in new-found affluence was expressed in attention to these lawns, and the characteristic American high valuation of private property rights was expressed in an especially proprietary attitude toward this real property.In the 1950s, '60s, and '70s, some of these first-generation homeowners were approaching or reaching retirement age, while the suburban-raised baby boomers were accustomed to the affluence symbolized by lawns as unremarkable.