Serenoa repens

saw palmetto

A three foot tall cluster of palmate fronds of a saw palmetto, Serenoa repens, in a garden bed at The Botanic Gardens at Kona Kai Resort in Key Largo, Florida

You may be familiar with this plant since it is found in grocery stores and pharmacies throughout the world as an herbal supplement, especially for the treatment of benign prostatic hyperplasia (BPH), which causes an enlarged prostate. Although some short-term (one year) clinical trials have been conducted with this plant to determine its efficacy, results have varied, so there is still debate. Personal testimonies after long-term use suggest that the plant is indeed effective to some degree. The supplement does not seem to actually shrink the prostate but seems to help urinary flow in other ways. Regardless of the actual efficacy of the herbal supplement, demand for the fruit is high and saw palmetto consistently ranks among the top 10 best-selling herbs.

A saw palmetto fruit stalk

In 1995, the raw fruit was being sold for over $3 per pound. Some Florida landowners have large populations of this plant in the understory of their pine forests and have reported instances of unwanted harvesters removing the fruits from the trees on their property in a few hours. Despite the attractive financial return these fruits offer, their harvest is hard to romanticize: “saw” is part of the plant’s name for a reason (spines line the leaf stems), fruits ripen in August and September (two of the hottest and most humid months in Florida), and the largest rattlesnake (eastern diamondback) likes to hang out in saw palmetto groves. I don’t know about you, but $3/lb. is not going to convince me to go stomping around places that happen to be hangouts for venomous snakes longer than I am tall. Here's a video about the business of harvesting and preparing saw palmetto fruits for the market:

The value of saw palmetto for medicine wasn’t always appreciated. Early European settlers wanted to use land to plant crops and pasture animals in the southeastern states and so needed to remove the saw palmetto. No doubt they would have first thought fire could easily solve the problem. Alas, they would have been greatly saddened watching the saw palmetto grow right back, since it is adapted to survive fires. Farmers then tried using plows and disc harrows to dig up the sprawling palms, which was effective but time consuming. I would have probably just packed up and moved somewhere in the Midwest where I would have had to clear prairie grass rather than saw palmettos.

Saw palmetto fruits are a valuable food source for wildlife and also used to be consumed frequently by the Seminole natives. The fruits have been described as “delicious and nourishing” and “comparable to nothing else but rotten cheese steeped in tobacco.” Hm. Regardless of taste, the fruits are a good source of fats, which are typically hard to come by in indigenous diets. Animals apparently can’t get enough of the fruit; a bear in Ocala National Forest was found to have ingested over thirty (yes, 30) pounds of saw palmetto fruits in a day...maybe they at least taste good to animals. In addition to using the fruits for food, wildlife also uses stands of the palm for protective cover and nesting.

I didn’t know much about palm flowers before moving to the Keys; indeed I thought the idea strange. Now I know much more about palm flowers, which are never very large individually but are borne in the tens or hundreds on large flowering stalks called inflorescences. Bees are attracted to the inflorescences of many palms, the nectar from which can be used to make distinctive high-grade honey, as is the case with saw palmetto.

The leaves were used by the Seminole in ways similar to how other indigenous peoples used the palms growing in their regions. These uses include baskets, brushes, rope, fishing nets and fire fans.

A very low-maintenance palm, this plant tolerates a variety of soil, light, and rainfall conditions, and is hardy north to Zone 8.