While driving today in Los Angeles I spotted these trees growing in the center of a roadway. The have green lichen on the trunk and huge thorns. Wonderful texture, but you would not want to lean against one! After some research on the net I found that they are Silk Floss trees, Cebia Speciosa. I wish I could be here to see them in flower. If you click on the photo's you can see a magnified view.