In natural areas at this moment are massive glistening clusters of shoebutton ardisia fruits. Wow is it prolific! The plant is a worldwide invasive exotic once grown in gardens, now a shrubby nuisance in natural areas. Don’t know if it is just “sampling error,” but I feel like I see more of it in Martin County and northward, than in PB County. In any case, there is plenty for everybody.
Shoebutton by John Bradford
Something I often wonder in the cases of invasive species with supernatural growth, as many seem to have, is, “isn’t there a way to harness that exuberance”? Biofuels, or food, fodder, fibers, or lumber, oils…some silver lining to each different invasive cloud.
The flowers by JB (not flowering now)
In the case of shoebutton ardisia, maybe medicines of the future, which is an over-worked theme perhaps in plant science, but this case seems so promising. Do not get me wrong, I am not suggesting using extracts from the plant for any purpose. No no no! Very likely toxic and dangerous. But maybe with continued research it could earn its keep. A diverse handful of unrelated plants produce a compound called bergenin. One is Caesalpinia digyna, a legume used traditionally to treat anxiety among other purposes. That is interesting because bergenin has emerged as a potential candidate as a natural antianxiety medication reportedly (one study) rivaling Valium (Diazepam) in effectiveness. Ardisias too produce bergenin, including A. elliptica.
Lots of berries
To get to the point then, shoebutton ardisia grows unwelcomely in Florida and around the tropical globe in crop-sized quantities on poor soils with no fertilizer, and makes billions of fruits. Wouldn’t it just be a fine thing IF bergenin turned out to be an effective and safe antianxiety med, and IF it could be sourced to redeem today’s rampant invader?
While beachcombing a few days ago for flowering nickerbean (found a couple), a stunning blossom surprised me directly on the beach sand glowing purple and yellow between my flip-flops: Beach-Peanut. Misnomer alert: not a peanut. What this species has in common with a peanut is it buries its fruit, pretty dang deep, generally between 4 inches and a foot. Then it somehow manages the miracle of sprouting way down there and penetrating to the surface, or the buried seed may wash away during beach erosion to find itself under shifting sands on a different beach. Perhaps Nicole relocated a few. As the “peanut” is pushed down through the abrasive sand, it forms a thick protective “helmet” on its downward end.
Look at this crazy plant burying its fruit!
The buried “nut” is in the lower left.
The species is rare in Florida, on a short stretch of the coastal East Coast, and extends southward onto tropical beaches beyond the Sunshine State. You don’t see it often, and never would if not for that eye-popping magenta flower. Oddly those purple petals are not petals, but rather fancy sepals.
By John Bradford
I wonder what pollinator visits it. Maybe nobody, because the tiny bit of study devoted to the biology of this species, in the 1970s, found two types of flowers: 1. The showy ones seem to be strictly functionally male, oddly having no recipient for their pollen because there seem to be no pollen-receptive female (or mixed sex) flowers. (They may have a stigma but it does not work.) 2. The second type of flower never fully opens. Instead, it self-pollinates while remaining shuttered and buries the baby.
This flower is functionally male-only. By JB.
So why make those big showy pointless male blossoms? I don’t know. Somewhere along the line something must have changed. Perhaps pollen-receptive flowers do (or once did) exist in the less-explored parts of the range on some remote Gilligan’s Island beyond Florida. If so, the seeds most likely to go forth and successfully colonize a new beach would be those that mature into self-pollinated individuals with assured solo reproduction. No partner from a second seed required. So then maybe Florida is home to a line of mutated self-pollinated diaspora escaped from a proper but undiscovered male-female population. As the last botanist who studied Beach-Peanut said, “this interesting genus requires further study.” Ya think?
A few years ago John and I botanizing on Hutchinson Island along the shore noticed a lot of Buttonwoods to have weird stunted growth characterized by vast numbers of stunted branches in tight clusters. This is more or less a “witch’s broom,” a broad term for deformations in various plant species caused by various “things” interfere with growing branchlets. If the growing tips are killed repeatedly, new growth comes forth, only to die, followed by more new growth, etc. etc. until you have a “broom.” Tip killers include smog, mites, microbes, herbicides, and who knows what else. I guess at the time, puzzled, we were superficially inclined to attribute the witch’s brooms to cold salty January ocean winds. The damage seemed worst on exposed trees. Maybe from nasty winds. Probably not.
Then over the last few days there it was again on Jupiter Island in the same type of seashore habitat several miles south of Hutchinson. Again the damage is widespread, conspicuous, and unevenly distributed. This renewed my curiosity.
Witch’s broom on Jupiter Island a few days ago
What do you do when you’re curious? Google! Doing that turned up deformed Conocarpus cultivated in Iran with the trouble attributed to a a pathological microbe. Could be something similar here but the Iran damage looks different from the Florida trouble. Unlike the case in Iran, I’ve encountered damage only on seashore individuals, as if maritime conditions are a factor either directly or as a stress, or merely chance, given that Conocarpus is a seashore species, so except for cultivation, seashore habitats are its home.
More Googling led to the UF/IFAS blog of a year ago 12 Nov 2021 by Michelle Leonard-Mularz showing damage identical to that Hutchinson Island and on Jupiter Island but much farther south, in the Keys, no doubt again near the sea, although less prone to cold January winds than Hutchinson Island and Jupiter Island. That blog attributed the witch’s brooms to the ALS inhibitor herbicides, for example Image, taken up by the roots.
Witch’s broom in the Keys from IFAS blog
That’s probably correct, although perhaps short of proven beyond the shadow of a doubt. The damage being near the sea casts a small shadow of a doubt, and I see the damage among mangroves where I don’t think there ought to be root-uptake herbicides, but you never know. In all cases there are roads nearby, with roadsides weeds conceivably suppressed the chemical way. This IFAS publication shows (Figure 4) stunting on a Conocarpus in a nursery pot, attributed to herbicide
In any case, time will tell more along the seashores where a lot of naturally occurring Buttonwoods are in obvious distress from Martin County to the Keys. When you get around that habitat, take a glance at the Buttonwoods, and be careful with the herbicides. The modern types kick ass.
Around Palm Beach and Martin counties are thousands of shallow depressions ranging from a few yards to hundreds of yards in diameter. A few hold water year-round. A few seldom-to-never hold standing water. Most are flooded during the rainy months, and droughty and crusty during the dry season. Most of the seasonally flooded depressions are dominated by two shrubs coexisting hand-in hand: Corkwood (Stillingia aquatica) and Peelbark St. Johnswort (Hypericum fasciculatum). These marshes don’t have a formal name, so I call them Hypericum-Stillingia marshes. They are an intriguing yet virtually unstudied ecosystem.
H-S marsh. Look how shrubs cluster around the tree bases.
What a harsh environment! Under water half the year, and a sun-baked desert the other half. Which season is worse… suffocating submerged roots in the summer-autumn, or dry-roasting the rest of the year? Every species must cope with both extremes, and each has its own mechanisms for dealing with the seasonal double whammy. Every species there has its own story. Let’s look at the key players: Hypericum and Stillingia.
Above, Hypericum. Below, Stillingia.
How does Hypericum survive the flooding? It has an extremely shallow roots system snaking around just under the surface, and little “snorkels” rising up into the standing water where there is dissolved oxygen.
Hypericum roots with snorkels
There are also stilt roots around the base of the trunk, able to capture oxygen even when there’s flooding below. They also capture algae and nitrogen-fixing cyanobacteria, which probably helps with mineral nutrition.
The same species in the hot dry season benefits skinny leaves resembling conifer needles, and from protective bark far thicker than that known on any other local shrub.
Stillingia aquatica differs by having, instead of wandering shallow roots, comparatively deep roots in a crowded mass, and with built-in air canals near the water surface.
Stillingia roots
The base of the root mass is deep enough to stay where the soil remains moist year-round, and the air canals up high handle ventilation. The leaves are narrow, and, like some desert plants (you know, cacti), the trunk has thick green tissue able to photosynthesize with minimal water loss. The flowers are far out in a marsh where pollinating insects are scarce. The strongest cross-marsh fliers are wasps, drawn from afar to the tuft of yellow bracts under the flowers, and fueled by little nectar goblets on the stem near the flowers. As is also true of Hypericum, in Stillingia if insects fail to bring pollen the plant pollinates itself as a reproductive safety net. Stillingia seeds are built for both seasons: they can float when flooded, and each has built-in ant food for ant assistance during dry times.
Yellow bracts
Nectar goblet
Stillingia seed with ant bait
A completely different set of woody species lives on the raised hummocks above the highwater line. The hummocks are masses of tree roots, mostly from Slash Pines, with accumulated organic debris and oodles of ants. Eight species “own” the hummocks: Cocoplum, Dahoon Holly, Muscadine Grape, Myrsine, Saw Palmetto, Smilax, Swamp Bay, and Wax Myrtle. What almost all have in common is small bird-dispersed fruits rained down by birds sitting in the Slash Pines. Most of the hummocks host masses of Wax Myrtle, which, as a nitrogen-fixing species, will be found by future ecologists to fertilize the other hummocks species.
Cyanobacteria = Blue Green Algae
Bird droppings from the pines are great sources of phosphorus. The plants are conspicuously extra-large near major bird nesting sites. What’s tricky to explain is that most of the hummock-dwelling shrubs (but none of the bottom-dwellers) are dioecious, that is, have separate male and female individuals. Reasons for this are unknown, although dioecy correlates with harsh seedling conditions, including shade. Makes sense, given that a completely female dioecious plant can specialize on making particularly tough shade-tolerant seedlings instead of using half its resources for male functions, making and dispersing pollen.
In short, the Hypericum-Stillingia marsh is a living laboratory of unusual nutritional relationships, odd root structures, unique pollination challenges, complex breeding systems, and adaptations to tolerate two environmental extremes in the same plants. On one hand, it is surprisingly how minimally these systems are known. On the other hand, I like the unexplored mysteries right under our noses. That’s what makes it all so much fun. Anybody can go to an Hypericum-Stillingia marsh and delve into the unknown for an hour.
Ant carton nest “treehouse” high and dry above the flood.
So often you go looking for one thing, strike out and find something else. While walking the local sandy coastline for other plants, I stumbled upon a beach dunes treat: Jacquemontia reclinata, a federally listed endangered species with no known footsteps outside of a few SE Florida counties, including Palm Beach County. Land management authorities don’t like reveals of where you can see endangered species, so suffice it to say Beach Clustervine has been previously reported where encountered in flower today, although “believed to be extirpated.”
Jacquemontia reclinata. All photos today by by John Bradford.
The disappearance doesn’t surprise me, because the species inhabits disturbed seaside sand where everything disappears. All kinds of things come and go where the waves crash, the sand drifts, and the briny breezes bluster. So I suspect that if all truth were known, Beach Clustervine may often be a “pop up species,” here today, gone tomorrow, back next year, or decade, or century. A quick look at occurrences on iNaturalist around SE Florida buttresses the notion. Incidentally, there have been reintroduction efforts, but I don’t know where.
That all leads to the main point. A creeping vine on seashore sand must have fantastic powers. First off, pollination could be a problem for a spotty species widely scattered in small patches in strong winds. But no worries, a wide array of insects visit. And as you might expect in a beach pioneer, the vine does not require pollinators, self-pollination providing reproductive assurance.
What I find intriguing is the poorly known unknown, the seeds. They obviously must float in the drink before washing up on a new beach and taking hold. Those must be some tough little seeds, and why Floirda but not the Bahamas? (Or is it lurking on one of many many beaches there awaiting discovery?) After washing up to be buried under shifting sand, the seeds must “lie low” until some moment of disturbance exposes them to their germination cues, perhaps some combination of air, light, and freshwater. Biologist John Pascarella and collaborators investigated the seed biology over the years 2001-2007. Soil cores revealed buried seeds waiting patiently in the seashore sand. Chemical testing showed a whopping 100% of year-old buried seeds to be alive. An interesting kink in that study was that even when buried seeds are all viable, not all germinate when presented with a set of seemingly favorable circumstances. Seems that different seeds have different triggers, some always in reserve for the many moods of the sea.
Worked with John this morning on our glacially progressing “photo guide to the native trees and shrubs of South Florida” project. In the wet pine woods along the drive home I beheld a beautiful sign of October in Florida. No, not pumpkin spice, but plume grass with plumes. There’s only a narrow window in time to enjoy that sight.
Plume grass spikelet by John Bradford
Plume grass comes in different geographically separate forms, and different populations even have different chromosome numbers, all multiples of 30. It has long been known that there is something “funny” about this species.
by JB
In recent years DNA has revealed plume grass as an ancient hybrid combining two ancestors: one ancestor is a close relative of sugarcane (Saccharum officinarum). The other ancestor according to one molecular study is a “silvergrass” in the genus Miscanthidium, not even found in the Americas, although the story is far from complete.
Today
And here’s another head scratcher. In North America plume grass appears largely to be cross-pollinated with normal flowers, but the species extends southward into Mexico and southward where “Saccharum giganteum” grades into a very similar relative, often called Saccharum trinii, in which the flowers self-pollinate and never open.
Been thinking backwards this week, starting with a visit from a face-to-face with a native long-tailed skipper butterfly sipping nectar from a non-native Pentas. Longtail skippers use legumes as larval hosts, thus the name “bean leaf rollers” for the caterpillars. An abundant host legume is the non-native Beggarweed, Desmodium inacanum. Although hard data are scarce, one seemingly well informed on-line writer attributes the abundance of the LT Skippers around Tampa to the plentitude of the urban-happy Beggarweed. Seems likely that the invasive exotic weed aids the lovely native butterfly. That all got me thinking about other cases where invasive exotic species may benefit native species. An invasive exotic we (almost) all love is the honeybee, although even beloved honeybees are not great for native pollinators. Buzz here
Can non-native plants in their unwelcome abundance help make up for their invasion by feeding native pollinators? That is a meaningful question, knowing that some native bee species are in decline, perhaps thanks in part to honeybees (and much more). Delving into that big complex question is more a topic for a major research project than a paragraph in a blog. Yet even so, the answer seems to be a qualified yes, at times, with the devil in the poorly studied details.
Don’t get me wrong. I’m not defending or advocating invasive exotics, which of course on balance are an environmental disaster. But they are here in spades, and I spend a lot of time out in the swamps and fields, finding it all interesting, including the good, the bad, and the ugly. Even when an invasive exotic boosts the population or range of a native species, that alteration in the balance of nature is not necessarily “good.” Even so, if hundreds of non-native species are out there impacting the native flora and fauna, let’s sniff out some positivity.
We all know that invasive predators crunching native prey is a terrible thing, such as invasive Cuban Tree Frogs eating native frogs, or pythons eating me. But do native predators leverage invasive exotic prey? Yes, speaking of pythons, there was an well-publicized case recently of native bobcats breakfasting on python eggs. CLICK And speaking also of Cuban treefrogs, several native snakes and birds, including owls, eat Cuban treefrogs.
Around local wetlands a conspicuous invasion is by the island apple snail, Pomacea maculata among additional non-native snails. The native Florida apple snail, Pomacea paludosa, feeds snail kites and limpkins. As the invasive snails have increased, limpkins have likewise increased, probably also true for snail kites. Little Blue Herons studied in 2017 in the Everglades had slightly over half their diet comprised of non-native fish.
What is the most despised invasive exotic tree in Florida? Cast your vote. Brazilian Pepper has over-run vast ecosystems, thanks in part to birds dispersing its red berries (drupes). Those helpful birds are feeding happily on those billions of exotic berries, although there are documented downsides to the indulgence. Beyond feeding (and sometimes intoxicating) native birds, Brazilian Pepper trees serve as rookeries, not to mention supporting pollinating insects, probably true also of Melaleuca.
I’m not sure about much in today’s blog, but I’m darn sure I love manatees and fret about the decline of native seagrasses they eat. I just looked it up, manatees eat almost my weight in aquatic veggies per day. Fortunately they are not fussy about native vegetation, because manatees munch pesky invasive exotic water weeds such as hydrilla and water hyacinth.
Take home lesson, except for mosquitoes and covid, nothing is completely evil.
So nice to get out into the flooded (Hurricane Ian) marsh after a long trip complete with Covid. A species comfortable in a flooded marsh is Glade Lobelia, blossoming now in a foot of water. Back in 2014 it appeared in this blog, but today we’ll focus on a different angle, the fancy way the flowers work in this and other Lobelia species.
Glade Lobelia by John Bradford
The male pollen-making anthers are united into a tube around the female pollen-receptive stigma. Think of me pulling on a turtleneck sweater: the anther tube is the sweater neck, and my head pushing through the tubular neck is the stigma. The combined anther tube juts out of the entrance to the flower.
Looking into the flower. The black unit at the center is the anther tube.Male and female unit removed from flower. The tube (matching the black in the photo above) is at the upper left, with two stigmas sticking out its tip.
Pollination happens in two phases, male first. At this first stage the anther tube produces pollen to its inside. The pollen is then plunged out of the tube by the rising still-unreceptive stigma. The pushed-out pollen is exposed at the tube tip to be picked up by floral visitors. A second force no doubt helping to squeeze the pollen forth may come from bees squeezing the anther tube while pushing past it to enter the flower. If you squeeze the tube with your fingers yellow pollen comes out the end like toothpaste from its tube.
Squeeze the tube and yellow pollen comes out.Male phase
After the pollen release, the female phase takes place as the stigma rises beyond the tip of the now-empty anther tube. Upon emerging from the end of the tube, the now- exposed stigmas spread out to accept insect-borne pollen from other flowers.
Female phaseDid somebody say bee-pollinated?
Self-pollination is avoided in Glades Lobelia by the separation in time of two phases. But in some species self-pollination is a “plus.” In Lobelia all that is needed for self-pollination to happen is for the stigma to become receptive while squeezing the pollen out. That is, allow the two phases to overlap in time. Nobody knows how often this situation has evolved, but there is one obvious case in Lobelia where the separation in time is documented to have broken down: In Lobelia inflata (Indian-Tobacco) the stigma is fertilized by self-pollen while still in the anther tube. That being so, the tube never opens, and the self-pollinated stigmas never emerge from it. Everything is self-contained.
The last week or two has been a good “stretch” for Ruddy Daggerwing Butterflies, something right now must agree with them. Sometimes you see Daggerwings in a shaded woods way up high bouncing in and out of the tree branch shadows. Sometimes they come down and say hello, feeding on any of many flowers. The larvae feed on Strangler Figs, as in my yard, likely the reason Daggerwings visit out the window during sunny morning coffee time.
The wings folded up look like leaves, when open they are orange and tiger-striped. The wings have a variable “swallowtail” even though Ruddies are not Swallowtail Butterflies in a taxonomic sense. Those “tails” must be useful because they have evolved multiple times. An idea not original with me, they seem to be false antennae that orient confused predators to the rear (less vulnerable end) of the butterfly.
Movie Feature, Rudy the ruddy finds bees bothersome: CLICK
Count the movie star’s legs. Insects have 6 legs, right? Not always; in this family (the brush-footed butterflies), only four legs are leggy, the other two reduced to sensory organs.
For the moment let’s agree with the many websites that state “the” larval host plants of the RDW to be Ficus. Around here natively that would be mostly Strangler Fig, Ficus aurea, plus some cultivated species. The butterfly is a “pest” on edible figs. Fig stems and leavess ooze milky sap, which may be key to an oddity of the caterpillars. They make a little “nest” of debris and frass probably glued with the milky goo, either fresh or after passing through the caterpillar. I have no idea why. As with so much of natural history….what’s up with that?
Everybody knows butterflies render themselves poisonous to predators by taking up toxins from their larval hostplants. Now in the case of the Daggerwings, that gets interesting. I don’t know how toxic Strangler Fig sap may be, but the butterfly extends tropically into South America where the larvae feed on a different member of the fig family called Naucleopsis (now-clee-OP-sis). Species of Naucleopsis in different regions are the secret sauce in lethal poison arrows and darts. Don’t eat any Rudder Daggerwings.
The northern range of Daggerwings is of interest too. Here in South Florida “the” larval foodplant may be strictly Ficus, but the range of the Ruddy Daggerwing extends westward and northward where no Ficus grows. Ruddy Daggerwings are recorded historically west beyond Texas and northward through Kansas and, decreasingly, much farther north. Lucky for us the British Museum of Natural History maintains records, available online, tabulating every known hostplant for every butterfly. A search there shows for Ruddy Daggerwing, not only Ficus and Naucleopsis, but also “Maclura.” That may be significant. When I was a kid growing up in West Virginia we used to throw ”monkey balls,” fruits of the so-called Osage-Orange tree, Maclura pomifera, yep, in the Fig Family. Osage-Orange wood is arguably the best North American wood for making bows, as in bows and arrows. For that reason pre-Europeans presumably moved the valuable tree around. Humans relocating its likely northern host may have extended the range of the Ruddy Daggerwing. I’ve always been drawn to the suspected influences of thousands and thousands of years of pre-Europeans in the modern ranges of plant species.
Come to think of it, speaking of bows and arrows, Daggerwings, and larval hosts the same may be true in South America for Naucleopsis.
Look at the two maps below. One is the present range of Osage-Orange, the other is the present and historical range of the Ruddy Daggerwings. Remember that the southern extensions into the tropics can be based on Ficus (and Naucleopsis). The northern similarities of the Daggerwing’s present and past range and the range of Osage-Oranges are suggestive. (The dark green dots are the area where the tree is common, the more widespread lighter dots show where it is spotty.) Wonder why the butterfly disappeared from part of its historical distribution: reduction in woodlands with Maclura? Increased or changing agricultural pesticide use? Glad we have it here.
Ruddy Daggerwing present and past distributionsMaclura. Bright green (Texas, Oklahoma, Arkansas = core of the range). Blue-green = counties where recorded but spotty.
I spend more time than the average retiree wading in Florida depression marshes. Messing around out there, a person notices some things. It is easy to notice widely scattered bright spots of red flowers…Narrowleaf Milkweed rising above the other vegetation. Another less-conspicuous observation is that far from shores pollinators become comparatively sparse.
Narrowleaf Milkweed with baby Queen, by John Bradford
Those two observations are no doubt linked. If you grow scattered and far from shores, pollinators may be a problem. And those limited pollinators need to find you, which is where those showy flower clusters pay off. The pollinators also need to be strong fliers to cover the extended distances.
Queen by Donna Rogers
On the second point, back in 2006 ecologists Derek Artz and Keith Waddington checked out exactly which long-distance visitors pollinate Narrowleaf Milkweed in South Florida. The three marathon winners were: Giant Swallowtail Butterflies, Phaon Crescent Butterflies, and Queen Butterflies. Paper wasps go the distance too but were not great Milkweed pollen carriers.
NL Milkweed habitat
What about the famous linkage between Monarch Butterflies and Milkweeds? I’m not saying that Monarchs never use Narrowleaf Milkweed as larval hosts or as nectar plants, but they were at least not in the long-distance winner’s circle. Monarchs and Narrowleaf Milkweed may have a slight mismatch with some limitations. First of all, Narrowleaf Milkweed is widely scattered and has skinny leaves, both points not optimal for the big voracious Monarch caterpillars that devour more productive crowded leafy Milkweeds. The skimpy food supply of the shoestring leaves probably disfavor Monarch caterpillars which become cranky and mutually aggressive when food is in short supply. A shoestring budget is no place for grumpy Monarch babies. Also, Monarchs make themselves toxic by ingesting poisons from the Milkweed the caterpillars eat. But turns out Narrowleaf Milkweed doesn’t offer much bang for your buck.
Encountered in the Milkweed habitat. Hope they ain’t human.
Queen Butterflies are closely related to Monarchs, and differ in ways that might make them a better “fit” with Narrowleaf Milkweed. Although Queen’s can take up poisons from Milkweeds, they are less likely too, so a relatively non-toxic Milkweed seems ok for them. They are a little smaller on average than Monarchs and may thus fare better on skinny and scattered larval hostplants. Also, although Queens and Monarchs both favor as larval hosts Milkweeds and close relatives, Queens have broader hostplant tolerances and may thus be less dependent on a rich crop of Milkweed out in the challenging marsh. The jury is still out somewhat, but it may be Queens and monarchs have some tendency at least proportionally to favor different Milkweeds. More research needed for a verdict.
Treasure Coast Natives 