The Mildred Mathias Botanical Gardens is located on the campus of the University of California, Los Angeles. It is considered one of the most important living botanical collections in the country and features plants from across the world. The space includes a seven acre garden that is able to exhibit a variety of tropical and subtropical plants due to its year-round frost-free status since 1948. The garden features about 5,000 species in 225 families. The garden is used as an experimental site for subtropical trees. The garden began in 1929 when the school began offering classes in Westwood. There were willow trees growing along the nearby creek bed and the dry hills in the area were great for growing sage scrub. In the 1950's, special sections of eucalyptus, gymno sperms, palms, aquatics, succulents, and camellias were added to the collection. A lathhouse was added to the grounds, as was a Botany Building and a permanent experimental garden. The facility was named the Mildred E. Mathias Botanical Garden in 1970 in honor of the contributions of UCLA professor Dr. Mathias. The Nest is an outdoor classroom with bench seating that was built in 1996 allows garden classes to get outside and learn in the botanical environment. The gardens are open Monday through Friday from 8 AM until 5 PM and on Saturdays from 8 AM until 4 PM.