> They far exceed our short little maybe 80-90 year span on this earth. I mean we're so temporary. But the trees, these ancient trees, they cannot be taken for granted. Because you cannot replace an old growth forest. > > Once it's gone it's gone for good. [Arborist Blair Glenn](https://youtu.be/epI3N53_Bw0?t=398) --- The following applies to the Los Angeles area of Southern California. ## Natives - [Quercus agrifolia](https://en.wikipedia.org/wiki/Quercus_agrifolia), California Live Oak, Coast Live Oak - [Quercus engelmannii](https://en.wikipedia.org/wiki/Quercus_engelmannii), Engelmann Oak, Pasadena Oak - [Juglans californica](https://en.wikipedia.org/wiki/Juglans_californica), California Walnut, Southern California Black Walnut - [Washingtonia filifera](https://en.wikipedia.org/wiki/Washingtonia_filifera), California Fan Palm ### Non-Natives - [Cedrus deodara](https://en.wikipedia.org/wiki/Cedrus_deodara), Himalayan cedar, Deodar cedar - [Pinus pinea](https://en.wikipedia.org/wiki/Stone_pine), Italian Stone Pine, Mediterranean stone pine, umbrella pine, parasol pine ### Invasives - [Ailanthus altissima](https://en.wikipedia.org/wiki/Ailanthus_altissima), Tree of Heaven, Chinese sumac - [Schinus terebinthifolius](https://en.wikipedia.org/wiki/Schinus_terebinthifolia), Brazilian Pepper Tree - [Ulmus parvifolia](https://en.wikipedia.org/wiki/Ulmus_parvifolia), Chinese Elm - [Washingtonia robusta](https://en.wikipedia.org/wiki/Washingtonia_robusta), Mexican Fan Palm - Eucalyptus spp. ### Understory shrubs - [Heteromeles arbutifolia](https://en.wikipedia.org/wiki/Heteromeles), Toyon, Christmas Berry, California Holly |