Only one kind of Palm tree is indigenous to Southern California. Others, imported since the Spanish missions, were established in the 18th Century. Canary Island Date Palms are still so popular in Beverly Hills, Las Vegas and the Arizona suburbs they can go for $20,000 when mature. Most of the local palms were planted early in the 20th Century, and in preparation for the 1932 Olympics. But now they are threatened by a deadly fungus--and by city planners who don't plan to replace them.