Syagrus romanzoffanum is often cold hardy down to 14 as well but if you have a grove of 10 trees you may loose from three to five of them. A lone Syagrus near webmaster's home - Northern California. Butia capitata can withstand severe desert as in Death Valley and are also very frost hardy Palms which can take quite hard frosts such as those which occur in Las Vegas Nevada. Native to Argentina, Fruit is used for liquor and jelly. Arecastrum romanzoffianum which is often found in a hybrid sterile form called butia X syagrus.
Different characteristics take form depending on the way it was crossed.
Las Vegas is full of the hybrid along the massive palm plantings of the strip. The leaves tend to be longer than Butia alone, more glossy and bright like the Syagrus but more rigid and less plumose than Syagrus. Syagrus is quite a bit more frost sensitive and although is grown in Las Vegas usually is killed off every few years. Syagrus grows fine in places such as Tucson AZ and north in California to redding with no problem. The seed is said to taste like coconut.