The name fits. There are few plants more majestic in the wilds of South Florida than the royal palm, or Florida royal palm if you prefer, Roystonea regia. Few things say tropics than the leaves of a royal palm swaying gently with the breeze. Throw in some sand and waves and you've got the perfect South Florida tourism ad.
Royal palms are absolutely massive, reaching 120 feet or more in height and having a trunk two feet in diameter. Its leaves can be 15 feet long and weigh as much as 50 pounds. The top of the tree can spread 25 feet. If sheer size doesn't give away the identity of this palm, then there is the glossy-green crown shaft that separates the leaves from the trunk. Royal palms are one of the few non-legumes that fix nitrogen to the soil.
Unfortunately, it's all too rare, at least in the wilds of South Florida. According to the Institute for Regional Conservation, it is found in 58 parks and natural areas but native to only five. Its range includes five counties but it's native to only three — Collier, Miami-Dade and Monroe. It's naturalized in Martin and Palm Beach counties. Naturalists in the 19th century found royal palm as far north as Lake and Volusia counties, but severe cold, clearing by settlers or a combination of the two led to its demise. Florida lists it as endangered. However, it is widely used in landscaping, which accounts for much of its presence. One oddity: the Institute for Regional Conservation considers royal palm to be potentially invasive in some areas outside its native range, making it both endangered and invasive, or at least potentially so, at the same time.
Royal Palm's range includes the Caribbean, Mexico and Central America. It is the national tree of Cuba, but is considered an invasive in parts of Panama.
It is a major source of nectar for honey bees, and provides roosting spots for the Florida bonneted bat. Other bats and birds eat the orange-red fruit the tree produces. The seeds also are a source of oil and feed for livestock. Those huge leaves are used as thatch, and the trunks are used for lumber in parts of its range.
Haitian immigrants to Cuba used the roots to make a drink called tifey (one of 30-plus herbal ingredients used). Some cultures make a diuretic from the seeds, which they also use to treat diabetes. Some research shows that an extract from the seeds is effective in treating benign prostate hyperplasia (an enlarged prostate, commonly known as BPH) in mice and could produce an alternative drug to current therapies.
Royal Palm's scientific name honors a nonscientist who as far as we know, made no contributions to botany. That would be Roy Stone, a Civil War general who was one of the heroes for the Union at Gettysburg. Stone later fought in the Spanish American War, building roads in Puerto Rico during the conflict. That work earned him the honor.
Royal Palm is a member of the Arecaceae family. It is also known as Cuban Royal Palm. Cuban and Florida royal palms were once considered separate species but are now classified as one. The Lady Bird Johnson Wildflower Center uses Florida royal palm as the common name. Synonyms — scientific names that have been used but are not accepted by authorities — include Palma elata, Roystonea elata, and Roystonea floridana