Serenoa repens, commonly known as saw palmetto, is the sole species currently classified in the genus Serenoa. It has been known by a number of synonyms, including Sabal serrulatum, under which name it still often appears in alternative medicine. It is a small palm, normally reaching a height of around 2–4 m (3–6 ft). Its trunk is sprawling, and it grows in clumps or dense thickets in sandy coastal lands or as undergrowth in pine woods or hardwood hammocks. Erect stems or trunks are rarely produced but are found in some populations. It is endemic to the southeastern United States, most commonly along the Atlantic and Gulf Coastal plains, but also as far inland as southern Arkansas. It is a hardy plant; extremely slow growing, and long lived, with some plants, especially in Florida where it is known as simply the palmetto, possibly being as old as 500–700 years.
Saw palmetto is a fan palm, with the leaves that have a bare petiole terminating in a rounded fan of about 20 leaflets. The petiole is armed with fine, sharp teeth or spines that give the species its common name. The teeth or spines are easily capable of breaking the skin, and protection should be worn when working around a Saw Palmetto. The leaves are light green inland, and silvery-white in coastal regions. The leaves are 1–2 m in length, the leaflets 50–100 cm long. They are similar to the leaves of the palmettos of genus Sabal. The flowers are yellowish-white, about 5 mm across, produced in dense compound panicles up to 60 cm long. The fruit is a large reddish-black drupe and is an important food source for wildlife and historically for humans. The plant is used as a food plant by the larvae of some Lepidoptera species such as Batrachedra decoctor, which feeds exclusively on the plant. This plant is also edible to human beings, but the more green it is the more bitter tasting it would be.
Medical Use 
The fruits of the saw palmetto are highly enriched with fatty acids and phytosterols, and extracts of the fruits have been the subject of intensive research for the symptomatic treatment of benign prostatic hyperplasia (BPH). This extract is also commonly used for other medical conditions, such as baldness, polycystic ovarian syndrome, and other hyperandrogen conditions, though research on such uses is preliminary.
Numerous meta-analyses of clinical trials S. repens extract in the treatment of BPH have found it safe and effective for mild-to-moderate BPH compared to placebo, finasteride, and tamsulosin Two larger trials found the extract no different from placebo. An updated meta-analysis including these trials found that saw palmetto extract "was not more effective than placebo for treatment of hyperplasia but following two million U.S. who use saw palmetto, urinary problems are greatly reduced. However, saw palmetto extract was comparable to tamsulosin and finasteride in this meta-analysis. Longer-term (2 years; most clinical trials have been 1 year) open studies suggest that saw palmetto reduces the risk of men with BPH ultimately needing to have surgery.
Indigenous names reported by Austin include: tala (Choctaw); cani (Timucua); ta ́:la (Koasati); taalachoba ("big palm", Alabama); ta:laɬ a ́ kko ("big palm," Creek); talco ́:bˆı ("big palm," Mikasuki); talimushi ("palmetto's uncle," Choctaw), and guana (Taino, possibly). Saw palmetto fibers have been found among materials from indigenous people as far north as Wisconsin and New York, strongly suggesting this material was widely traded prior to European contact. The leaves are used for thatching by several indigenous groups; so commonly so that there is a location in Alachua County, Florida named Kanapaha ("palm house"). The fruits may have been used to treat an unclear form of fish poisoning by the Seminoles and Bahamians.
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- "Serenoa repens (W. Bartram) Small". Germplasm Resources Information Network. United States Department of Agriculture. 1997-05-22. Retrieved 2010-04-12.
- Barnard, Edward S. & Yates, Sharon Fass, ed. (1998). "Trees". Reader's Digest North American Wildlife: Trees and Nonflowering Plants. The Reader's Digest Association, Inc. p. 131. ISBN 0-7621-0037-0.
- Tanner, George W.; J. Jeffrey Mullahey; David Maehr (July 1996). Saw-palmetto: An Ecologically and Economically Important Native Palm (PDF). Circular WEC-109. University of Florida Cooperative Extension Service.
- Prager N, Bickett K, French N,Marcovici G (2002). "A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of 5-a-reductase in the treatment of androgenetic alopecia". J Altern Complement Ther 8: 148–52. doi:10.1089/107555302317371433. PMID 12006122.
- Wilt T, Ishani A, Mac Donald R (2002). "Serenoa repens for benign prostatic hyperplasia". In Tacklind, James. Cochrane Database Syst Rev (3): CD001423. doi:10.1002/14651858.CD001423. PMID 12137626.
- Boyle, P; Robertson C, Lowe F, Roehrborn C (Apr 2004). "Updated meta-analysis of clinical trials of Serenoa repens extract in the treatment of symptomatic benign prostatic hyperplasia". BJU Int 93 (6): 751–756. doi:10.1111/j.1464-410X.2003.04735.x. PMID 15049985.
- Bent S, Kane C, Shinohara K, et al (February 2006). "Saw palmetto for benign prostatic hyperplasia". N. Engl. J. Med. 354 (6): 557–566. doi:10.1056/NEJMoa053085. PMID 16467543.
- Dedhia RC, McVary KT (June 2008). "Phytotherapy for lower urinary tract symptoms secondary to benign prostatic hyperplasia". J. Urol. 179 (6): 2119–2125. doi:10.1016/j.juro.2008.01.094. PMID 18423748.
- Tacklind, J; MacDonald R, Rutks I, Wilt TJ (April 2009). "Serenoa repens for benign prostatic hyperplasia". In Tacklind, James. Cochrane Database Syst Rev (2): CD001423. doi:10.1002/14651858.CD001423.pub2. PMC 3090655. PMID 19370565.
- Djavan B, Fong YK, Chaudry A, et al. (2005). "Progression delay in men with mild symptoms of bladder outlet obstruction: a comparative study of phytotherapy and watchful waiting". World J Urol 23 (4): 253–6. doi:10.1007/s00345-005-0005-7. PMID 16175413.
- Austin, DF (2004). Florida Ethnobotany. Boca Raton, FL: CRC Press. ISBN 978-0-8493-2332-4.
- Whitford AC (1941). "Textile fibers used in eastern aboriginal North America". Anthropological Papers of the American Museum of Natural History 38: 5–22.
- Simpson, JC (1956). A Provisional Gazetteer of Florida Place-Names of Indian Derivation. Tallahassee: Florida Geological Survey.
- Sturtevant, WC (1955). The Mikasuki Seminole: Medical Beliefs and Practices. Ann Arbor, MI: University Microfilms.