The pollen clouds typical in panhandle Florida’s spring have at last departed. The yellow, sneeze-inducing dust has given way to other aerial occupants of a much larger magnitude.
Of course, there are a variety of insects now active during the warming days and nights. Lovebugs in the former and mosquitoes in the latter make their presence known, usually to the irritation of anyone in close proximity.
Another airborne presence currently making itself known is sometimes considered a landscape annoyance. Thistledown, the nearly weightless fibrous material, is spreading seed on the spring breezes.
Locally, two genera of native and exotic plants employ this fluffy pulp to scatter their next generation to new germination sites. As the common name implies, thistles produce thistledown, but so do dandelions.
The feathery thistledown will soon relocate the seeds of thistles and dandelions to new locations. While often an uninvited plant in the home lawn, both plants support a variety of beneficial insects and animals.
North Florida’s thistles, both native and exotic, emerge early while many other plant species are dormant. Only a relatively few native plants are capable of reacting positively to the unforgiving cold nights by getting a botanical jumpstart on their competition.
The head start gives the thistles a major advantage for colonizing new ground and pushing out competing plants when the warmer season arrives.
There are at least nine different species of thistle in Florida which include tall thistle, Lecontes thistle, swamp thistle, Nutalls thistle, purple or yellow thistle, bull thistle, and Virginia thistle. They are distinguished by their flower’s color and the general shape of the plant, but several are rare and not commonly seen.
All Florida thistles are biennials, with the exception of Lecontes thistle which is a perennial. Biennial plants are those growing from seed in the first year and which produce seeds the second year.
There are three distinct life stages pertaining to all native thistles. During the first year the plant will grow as a rosette, a taproot with a cluster of leaves on or near the soil surface. The rosette growth stage occurs primarily during the winter months in north Florida.
During the second year, a stalk with a bloom bud will elongate from the rosette, which is referred to as bolting. Bolting frequently begins in late January and goes through July, depending on the species and environmental conditions.
Once the biennial plant blooms, it can produce up to 4,000 seeds per plant. The tiny seeds are dispersed under the soft feathery material as the thistle plants are dying.
Dandelions, the other thistledown producer, are also a cool season, hardy weed capable of handling panhandle Florida’s winters with little negative effect.
The hollow flower stalks form a single compound flower of many bright, golden-colored florets. Like chicory, varieties differ in leaf shape, ranging from very curly leaved to broad leaved.
It has low spreading, deeply notched leaves which form a rosette pattern as they emerge from a weak central tap root. It closely resembles the vegetable endive in form and in cultural requirements.
This time of year, after its flowering is finishing up, the dandelion’s flower head dries out for a few days. The bloom petals and stamen sluff off and the downy ball opens into a full sphere.
On the positive side, both plants support insect pollinators with nectar, pollen and foliage consumed by their caterpillars. Also, birds utilize the thistledown as nesting materials.
So, when either of these weeds “blemishes” the perfect landscape, understand they are supporting the local ecosystem. They will disappear as the thermometer (and the cooling bill) rises.
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