Natural History: The Sweet Smell of Saw Palmetto

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Annual saw palmetto flowering and fruiting are significant ecological events that attract hundreds of insect species, and provide food for bird and mammal species.

Mary E. Carrington, et. al., Pollination Biology of Saw Palmetto in Southwestern Florida, Palms, Volume 47(2), 2003

The sweet fragrance of saw palmetto at Oslo Riverfront Conservation Area (ORCA) —and at other conservation areas — perfumes the air for many weeks. Each densely branched inflorescence has hundreds, if not thousands, of flowers. The tiny flowers with 6 pollen-bearing anthers (visible in the photo below) open over the course of about a month from the base to the top.

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Saw palmetto is an “early bird”. Over half of its tiny flowers open between 2AM and 4PM, very few open up between 4AM & 7AM, and about 40% open between 7AM and 1PM, according to research conducted in Collier County by Mary Carrington and her colleagues. Lots of nectar was available on the first and second day, but declined in abundance on the third and fourth days. After the 4th day, the flowers browned and withered.

Its fragrance, nectar rewards, and sticky pollen attract more than 300 species of pollinators, according to Dr. Mark Deyrup, Senior Research Program Director and Research Biologist at Archbold Biological Research Station. Carrington found in her study that 80% of the insect visitors were from the orders hymenoptera (ants, bees, wasp & sawflies), and diptera (flies, mosquitoes). Bees, she opined, were “the primary pollinators”. Bees – native and European – carried large loads of pollen and visited multiple inflorescences, crawling over multiple flowers potentially pollinating older flowers that no longer had nectar to offer.

A southern carpenter bee (Xylocopa micans) is shown below reveling in the midst of saw palmetto flowers …

Love bugs (Plecia nearctica), love saw palmetto, too. Love bugs, which are non-biting flies, emerge in large numbers twice a year, usually in May and September. May is when saw palmettos flower, and love bugs, sometimes in large numbers, often are found, singly or coupled, crawling over saw palmetto flowers foraging for nectar or just lazing about for hours …

Saw palmetto deserves more respect as an important pollinator plant and as a source of food for birds and mammals.