Nearly 10% of Singapore's land has been set aside for parks and nature reserves. The network of nature reserves, parks, park connectors, nature ways, tree-lined roads and other natural areas have enhanced the sense of green space in the city.[93] This is a result of five decades of greening efforts, which began in 1963, when Prime Minister Lee Kuan Yew launched Singapore's first tree-planting campaign by planting a mempat tree (cratoxylum formosum). The aim was to soften the harshness of urbanisation and improve the quality of life.[94] This initiative continued into the 1970s and 1980s under the Parks and Recreation Department (PRD), renamed the National Parks Board (abbreviation: NParks) in July 1996.