(adults) and 'grazing' (larvae) plants that attract migrating butterflies. Mexican Columnar Cactus Garden – tall columnar cacti sculptural specimens. Ocotillo Garden – nine of twelve known ocotillo species. Opuntia Garden – various prickly pear (Opuntia) and cholla (Cylindropuntia) plants. Palm Garden – several hundred palm (Arecaceae) trees, of over fifty species from around the world. Primitive Garden – plants from the Jurassic period – cycads and ferns. Sage Garden – Salvia species of melliferous flower honey forage sage plants. Sheep Food Garden – plants that are food sources for desert bighorn sheep. Smoke Tree Garden – local native smoke trees (Psorothamnus spinosus) in a natural desert wash setting. Sonoran Arboretum – trees from the greater Sonoran Desert region in a designed garden setting. Wortz Demonstration Garden – Southwest landscape design display garden. Yucca Garden – Yucca species in a designed 'strap foliage garden. Other features The Zoo and Gardens featured one of the world's largest LGB model railroad layouts, with of the track. The world's longest wooden G-scale model trestle () lets trains travel between the upper and lower portions of the wash in which it was built – an almost drop. The trains started in 1998 as part of the annual WildLights holiday program and ran only in the evenings. In 2000 the trains started running throughout the year and during the day and at present there are 18 separate train lines that can run simultaneously. The trains and track are managed by an all-volunteer team. The Living Desert Zoo and Gardens features nature and hiking trails accessible only to members and visitors of the Park. Wildlife Wonders Show is seasonally offered and features free-flight birds, animal demonstrations, and encounters. See also Moorten Botanical Garden and Cactarium List of botanical gardens in the United States Index: Flora of the California desert regions Notes External links Organizational Profile – National Center for Charitable Statistics (Urban Institute) Botanical gardens in California Colorado Desert Coachella Valley Flora of the Sonoran Deserts Gardens in Riverside County, California Buildings and structures in Riverside County, California Tourist attractions in Riverside County, California Zoos in California Zoos established in 1970 Palm Desert, California Cactus gardens