NAPLES - Although it has been around longer than most Florida residents, the persistent groundcover that makes area lawns appear to be dusted with snow may not be a native plant after all.
Not long after the Dec. 31 "In the Know" column on this subject was published, I was told that there is more to the story. James R. Snyder of the U.S. Geological Survey's Florida Integrated Science Center at the Big Cypress National Preserve Field Station in Ochopee said the plant is exotic, not native. He sent me the following letter:
"Mr. Aten, I enjoy your column; it often answers questions about things I see about town. However, I would like to make a few corrections to your answer about the frosty lawns in today's column. I have lived in the Golden Gate Estates area off White Blvd. since 1985. I am a plant ecologist by trade and, therefore, pay attention to the plants around me. The plants with the star-like lavender flowers were not around in any appreciable numbers back in '85, but there has been a population explosion in the last several years so that I look forward to the seasonal color during the dry season.
"The plant is, in fact, Richardia grandiflora, and it is not native to Florida. It is now found pretty commonly in the southern half of the Florida peninsula. The plant is native to South America and is a widespread tropical weed. The somewhat artificially created common name for the plant is Largeflower Mexican Clover, thereby distinguishing it from Richardia scabra, which is Rough Mexican Clover, a weed also not native to Florida but with a broader distribution in the southeastern U.S. and whose flowers are not as large and showy as those of R. grandiflora."
Another reader sent me a note to say that the University of South Florida lists all four species of the Richardia genus as non-native. Upon checking the USF Institute for Systematic Botany's Atlas of Florida Vascular Plants, http://florida.plantatlas.usf.edu/, I found that to be correct.
"The difficulty comes in the definition of ‘native,' he writes. "In some definitions, Melaleuca would be a native. I've never seen any Richardia in the wild. ... only in ‘disturbed areas.' You might want to check with your plant expert again for a clarification."
So, I made another call to Cathy Feser, an urban horticulture extension agent with the University of Florida Collier County Extension Service. She agrees that the difficulty in this case may be in defining native.
"Everyone has a different definition of everything," she said.
Feser maintains that Richardia scabra is the scientific name for the species that produces the tiny white or lavender flowers on lawns throughout Southwest Florida and the entire state. It is native from North Carolina to South America, she said.
"When we talk about native plants, we are talking about native to North America, not necessarily native to Florida," Feser said. "The definition we go by in the Native Plant Society is that any plant that was here when Columbus landed. This business about Florida native, you can forget that."
The Florida Native Plant Society admits on its Web site to the complexity of defining native, which it reserves for plants in Florida before the "European ‘Ecological Imperialism' marked the drastic alteration of the indigenous flora of the peninsula."
"What is a ‘native' plant? This question, while on the surface quite simple, upon further examination reveals a greater degree of complexity than first imagined," according to the Florida Native Plant Society site. "In the botanical sense the meaning of "Florida Native Plant" and a precise definition is somewhat elusive."
According to the USDA's Natural Resources Conservation Service plants profile database, Richardia scabra, or rough Mexican clover, is listed as native to the Lower 48 states and Puerto Rico, and introduced in Hawaii. But the USDA lists Richardia grandiflora, or largeflower Mexican clover, as being introduced in the Lower 48, meaning it is not native.
Both of these species of the Richardia genus are prevalent in this region, so in addition to the native question, it may make a difference which species and which authority is referenced.
While I enjoyed seeing the local collaboration effort on this issue, I'm disappointed that it couldn't be boiled down to a definitive answer. Like it or not, whether those pretty flowers on your lawn are natives or exotics, they are still just tropical weeds.
Tim Aten is managing editor of optimization for the Daily News. E-mail questions with your name and city of residence to firstname.lastname@example.org.
Find a complete archive of "In the Know" at naplesnews.com/intheknow/
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