Orcutt Ranch was the vacation and retirement estate of William Warren Orcutt, an early pioneer of oil production in California and the discoverer of one of the first prehistoric skeletons at the La Brea Tar Pits. The Rancho Sombra del Roble, Spanish for "Ranch of the Shaded Oak", was originally a 210-acre (0.85 km2) cattle ranch and citrus orchard at the foot of the Simi Hills. Orcutt bought the property in 1917, and hired architect L.G. Knipe (who designed some of the original campus structures of Arizona State University) to design his home on the ranch. The 3,060-square-foot (284 m2) residence, in the blend of Spanish Colonial Revival Style and Mission Revival Style architecture, was completed in approximately 1926. It features glazed tiles from Mexico and carved mahogany and walnut from the Philippines. Visitors are surprised to find that the design of the home prominently incorporates bas-reliefSwastika architectural decoration. Mary Orcutt, William's wife, chose the symbol due to its connection with Native American traditions, and did so before the Nazis turned it into a symbol of anti-Semitism and genocide. President Herbert Hoover, who was a friend of the Orcutts, visited the ranch.
A 24-acre (10 ha) portion of the original estate, including the residence, gardens, oaks and citrus orchard, was designated as a Historic-Cultural Monument in January 1965. Those 24 acres (10 ha) were purchased by the City of Los Angeles in 1966 for $400,000. The 24-acre (10 ha) city-owned property includes a Spanish-style adobe residence, extensive gardens, oak trees hundreds of years old, Dayton Creek, nature trails, fruit orchards, rose gardens, community garden plots, picnic tables and a multitude of exotic trees, plants and shrubs. Some of the more unusual trees found at the ranch are Purple Lily Magnolias, Lady Palms ( Raphis excelsus ) native to Asia, Bunya Bunyas ( Araucaria bidwillii ) evergreen native to Australia with cones weighing up to 15 pounds (7 kg)), Cork Oaks ( Quercus suber ), and one of the many Coast Live Oaks ( Quercus agrifolia ) measuring 32 feet (10 m) in circumference, believed to be 700 years old. For 53 years (1927–1980), Ernest Conrejo was employed as the property's caretaker and gardener. Cornejo was hired at age 17 to plant and tend to the exotic trees and plants; he continued in that job until he was ousted at age 70 from his lifetime home by the city.
The Los Angeles Recreation and Parks Department operates Orcutt Ranch, which is available to be rented for special events. It is also opened up for popular public fruit picks.