St. Augustine grass (Stenataphrum secundatum) – no matter what you think about its landscape use — is not an invasive exotic pest plant.
St. Augustine grass, according to the Florida Plant Atlas, is native. The Florida Plant Atlas is maintained by the University of South Florida and is regarded as the authoritative resource for botanical names, plant distributions, and native (or exotic) status.
The Florida Exotic Pest Plant Council (FLEPPC), a volunteer organization of land managers, university researchers, and other concerns citizens, publishes a list of invasive exotic pest plants every two years. This list is not meant to be regulatory.
FLEPPC defines an exotic plant as “a species, introduced to Florida, purposefully or accidentally, from a natural range outside of Florida”. St. Augustine grass is NOT on the FLEPPC list because it is native.
Yes, St. Augustine grass is aggressive and can become weedy. Other native plants are called weeds when they grow in the wrong place, often aggressively.
What is a weed? The simplest definition: A plant growing in the wrong place. An exotic plant — or a native plant — can be a weed.
Let’s use the term exotic pest plant as intended: For plants that come from a natural range “outside of Florida”.
Reserve the term invasive pest plant for exotic invaders like the pernicious vining fern, old world climbing fern (Lygodium microphyllum) pictured above, that overtakes our natural areas.
Muddled logic is never helpful.