California State University, Northridge
OP-10: Biodiversity

Prior to the 19th century a diverse ecosystem structure of native flora in the Mediterranean biome, including open woodlands, low growing shrubs, and grasslands, existed in the San Fernando Valley. By the mid-late 19th century native trees had been largely eliminated to make room for ranches, crops, and orchards. In 1958, citrus and avocado orchards were cleared and the campus of San Fernando Valley State College (now California State University, Northridge-CSUN) was developed. Today, CSUN has over 4000 trees of 206 different species. In 1989 Robert Gohstand worked with students in the department to produce a plant atlas, identifying and mapping campus trees and shrubs. In 2011, this inventory was updated by Professor and former Director of the Institute for Sustainability, Dr. Helen Cox. Since then, CSUN Grounds has kept a detailed list of all trees purchased and planted. In fall 2018, Erica Wohldmann, Professor and Interim Director of the Institute for Sustainability, worked to categorize the trees on campus as either common, threatened, rare, endangered or invasive. Primary resources for tree identification and categorization included: the International Union for Conservation of Nature website, a comprehensive list of threatened species; CalFlora, a comprehensive search engine for native and invasive plants that grow in California; and students and faculty in the Biology Department. For many species, the scientific name has changed, posing a challenge to proper categorization. As of November 2018, approximately half of the trees have already been categorized, and the process will continue spring 2019.

Of the species that have been identified and categorized, 73 species (2255 trees) are native and/or common, 15 species (188 trees) are threatened, 10 species (135 trees) are endangered, and 2 species (6 trees) are critically endangered. In addition, 3 species (111 trees) are considered invasive.

Since 2014, CSUN has been designated as a Tree Campus USA by the Arbor Day Foundation. This program recognizes college and university campuses that effectively manage trees and engage students. As such, we established a Campus Tree Advisory Committee comprised of members representing the diverse audience of those with a stake in campus trees. The committee members provide guidance for planning, campus and community education, and the development of tree planting activities. Dr. Wohldmann collaborates regularly with key stakeholders responsible for tree care and maintenance on campus, including the Director of Energy and Sustainability, the Director of Grounds, Custodial and Events, and the Grounds Manager, all of whom work for Facilities, Planning, Design, and Construction. Once the inventory is completed, these stakeholders will work with the Campus Tree Advisory Committee to determine how to ensure threatened and endangered species are managed properly.