San Francisco Bay Area National Parks Science and Learning 2008 and 2009
"The Golden Gate National Parks Conservancy (GGNPC) operates six native plant nurseries in the Golden Gate National Recreation Area. These nurseries aim to produce genetically appropriate, healthy, weed and pathogen free plants for habitat restoration efforts in the park while having the smallest possible environmental impact. The nurseries have grown more than 400 native plant species, and they usually produce around 170,000 individual plants each year."