Last Friday John and George trekked the Trail to the River (CLICK), also known as the Halpatioke Nature Trail, a biodiverse satellite of Savannas State Park, in Port St. Lucie.
One of the many handsome marvels on the way to the river is Partridgeberry (Mitchella repens), which I’m sorry, I can only regard as a wildflower from childhood Canadian canoe trips, not a South Florida trail flower. It just doesn’t fit my world view here!
Also along the path are several members of a plant clique referred to by botanists as “DYCs.” DYC stands for, “darned yellow Composites,” and apt term for anyone who has tried to sort out yellow-flowered members of the Aster Family. Now please remember the “flowers” in the Aster Family are not real flowers, but rather are clusters of hundreds of tiny flowers all massed into one big false blossom. A Sunflower is a whole lot of flowers. (Details on this are in our archives CLICK)
The King of the DYCs Friday was Narrow-Leaf Sunflower (Helianthus angustifolius), with the lesser Smallfruit Beggarticks (Bidens mitis) as its loyal vassal.
If everything that could be known about Sunflowers were suddenly revealed it might boggle our brains. They are a group with a lot goin’ on. Technically, Sunflowers are the genus Helianthus, of which there exist roughly 50 species, all native to North America including Mexico. About 18 species grow “wild” in Florida, natively or escaped. From a taxonomic standpoint, they are messy messy messy, with hybrids, ancient and new cultivars, chromosomal variants, intermediates, unclear species borders, and divergent classification interpretations.
The big familiar common sunflower is Helianthus annuus, distributed “naturally” from Mexico to Nunavut. Ancient peoples no doubt helped its transcontinental spread and diversification. How many native American plant species have achieved agricultural prominence? Native American humans used it for almost every use conceivable. Arguably the most interesting ancient uses were culinary, for “seeds,” ground flour, and oil. There were probably large-seeded (achenes) cultivars in pre-settlement “horticulture.”
We like sunflower oil today, but a funny thing happened along the way. After an early history of cultivation in North America partly for livestock forage and chickenfeed, Sunflowers fell of out of agricultural favor but caught on in Russia as an oil crop. Oil-bearing strains returned to the U.S. from Russia with love in the 70s, and may help our grandchildren’s energy deficit someday.
Another sunflower with ancient “roots” is the so-called Jerusalem Artichoke (Helianthus tuberosus) distributed across much of North America, including some of Florida. What does it have to do with Jerusalem or artichokes? Its tuber is a food source and a source of combustible alcohols.
A garden favorite in Florida and far beyond is the Beach Sunflower, Helianthus debilis, easy to grow and as pretty as a day at the beach. Amazingly, this highly diverse foot-tall species can hybridize with the big common sunflower. (See what I mean about messy species boundaries?)
But what about our Sunflower along the trail to the river? Narrowleaf Sunflower (Swamp Sunflower, H. angustifolius) is a wildflower and a garden selection CLICK. The flower extends northward and westward from Texas to New York from a southeastern limit probably near the trail to the river.
Narrowleaf SF is a chemical factory. Aster Family members in general produce an array of smelly and bioactive compounds, so any given species can be a chemist’s goldmine. Narrowleaf Sunflower has attracted recent attention most importantly for cytotoxic (cell-killing) agents with lethal effect against cultured human cancer cells. CLICK This general sort of screening and discovery is not rare, but in an already much-cultivated prolific plant it’s even better. That would be a parallel history to the life-saving Oncovin chemotherapy from the Madagascar Periwinkle.
Even if Narrowleaf Sunflower turns out not to counter cancer, or even if it does, it feeds bees in spades. UF Entomology Professor Jaret Daniels describes native bees filling the pollination gaps left by non-native honeybees diminishing from Colony Collapse Disorder, and he points out native wildflowers drawing on average 19 times as many bees as non-native blossoms. Even better, he lists nine super-charged bee-feeding wildflowers. Five of the nine are DYC’s, including Narrowleaf Sunflower.