Red Spiderling

Boerhavia diffusa

Nyctaginaceae

Every time John and George go to the Hobe Sound National Wildlife Refuge calamity strikes.  Last time, we got the car stuck in the sand; today it was merely a downpour a mile from the car (parked safely on nice firm pavement).  We explored a dirt path immediately behind the seashore dunes, and marveled at the biodiverse lush dune  jungle .  Trying to compile a list of every plant species present would be a big effort because there are more species than I can count on my fingers and toes.  Interestingly, species associated with xeric habits (such as Cacti) are nearly adjacent there to others usually associated with wet feet (such as Fall Panicgrass).

Yellowtops (JB)

The lion’s share of the biomass is legumes, probably owing to their ability to create nitrogen “fertilizer” on otherwise poor sand:  Nickerbean (the dominant species) along with Baybean, Bushbean, Coinvine, Coralbean,  Cowpea, an invasive Senna species, and assorted  weeds represent the Bean Family.  Looking beyond Legumes, especially beautiful were the Yellowtops, Devil Potato, and Bloodberry.  But let’s get to the point.  A curious little species not rare on sandy soils is Red Spiderling (Boerhavia diffusa).

Spiderling (JB)

It’s pretty if you look closely, with Bougainvillea-colored flowers.  The coloration is no coincidence, as the two are in the same family.

Spiderling flowers and fruits (JB)

The Boerhavia flowers actually look like Bougainvillea flowers overall, but a point of clarification:  in Bougainvillea the flowers are small (not so different in size from Boerhavia) and white, the purple in Bougainvillea is in the bracts surrounding the flowers.

Garden Four-O-Clocks (Mirabilis) are likewise related with similar pigments, or to be more native-plant-oriented, likewise for Beach “Peanut” (Okenia hypogaea).

Okenia (JB)

The fruits in B. diffusa have sticky Velcro-hairs, and they do get around, in part with help from migratory birds.

Sooty Tern with Spiderling fruits along for the ride.  Sooty Terns are sea-faring birds.  (By botanist Sherwin Carlquist)

Variably defined, B. diffusa, or a complex of closely allied species, depending on how you split and lump,  is worldwide, including Asia, Africa, Hawaii, Australia, the Caribbean, and the U.S., with the point of origin unclear.  The relationships among the different interconnected variants is so unclear that estimates of the number of recognized species in the genus range from 10 to 40.  Or, worse, down through botanical history over 200 species names have been applied in Boerhavia.  In short, an extremely confusing genus where the species have not read the textbooks concerning species definition.

The plants have taproots, and these have served medicinally, including to prepare laxatives and expectorants.   Fact is, Boerhavias have served in many cultures worldwide in more medicinal capacities than Dr. Oz.   Alkaloids in the root, including an alkaloid called punaravine, are diueretic and raise the blood pressure.  The leaves are salad in some cultures, and the “seeds” have been ground into flour.  However, the alkaloids, bioactivity, and probable toxicity say do not eat this plant.

As as fascinating note added post-publication, Paul Rebmann at wildphoto.com (comments below) put the plant together with the Spiderling Plume Moth.    Click on the web address below to see flower and pollinator united at Paul’s site!  http://www.wildflphoto.com/species.php?k=a&id=300

 

Sea Blite and Castaway Plight

Sea Blite

Suaeda linearis

Amaranthaceae (Chenopodiaceae)

John, I TOLD you to turn right.

Yesterday John and George mired the car hopelessly in the seaside sand lost in the remote reaches of the Hobe Sound National Refuge, all in a day’s work for fearless adventurers.   It happened right as I said, “that sand looks firm.”  We became stranded castaways deep in a mangrove jungle unvisited by humans since Jonathan Dickinson.  While we stressed over who might find our buzzard-picked remains, we kept our spirits up by exploring the salty-marly mangrove lowland behind the dunes and singing marching songs from the Boer War.  We looked for esculent native plants to mitigate our stranded plight.  There wasn’t much to hunt and gather, but Black Mangrove was lovely in flower, and no, that wasn’t a skunk, it was White Stopper.

Our destitution gave us time to ponder convergent evolution.  (That is when unrelated species develop similarities due to similar adaptations.  Sharks and Porpoises are not related but they look similar.)  We saw no sharks nor porpoises, but we did see how salty-place plants have a convergent tendency toward succulent leaves that look like fingers.  The fat-finger-foliage species include Batis maritima (Saltwort, Batidaceae),  Salsola kali (Amaranthaceae), Sesuvium portulacastrum (Sea-Purslane, Aizoaceae), Salicornia bigelovii (Glasswort, Amaranthaceae), and Suaeda linearis (Sea Blite, Amaranthaceae).

Yes, the foliar similarities can confuse identification.  And yes, they confuse common names.  The common names for these species are intertwined and contrived.  For example, Batis maritima and Salsola kali (and undoubtedly others) get called “Saltwort,” hence the silly misleading name “Russian Thistle” to differentiate Salsola.  My personal outlook—never get too fixated on the English names for non-prominent plants.

The main succulent finger species yesterday was Suaeda linearis,  representing  the mostly saline genus Suaeda which has over 100 species.   As is often true of coastal species, the distribution is wider than you think.  Suaeda  linearis extends from Maine to Mexico and southward.  Such species keep us from getting too hung up on latitude.

Suaeda linearis (JB)

Suaedas inhabit saline desert areas in North Africa, where  Beduins burn the foliage to obtain soda-ash (sodium carbonate)  for laundering,  dying clothing, and fine-tuning the pH in their pools.  And speaking of burning  Suaeda, North Africans burn the plants also to generate smoke for asthma relief.  Suaeda is an ancient Arabic name.

Close-up (JB)

Closer to home, Native North Americans appreciated the seeds as a staple grain, which was a comfort to John and me as we despaired of rescue yesterday.  As we roasted fiddler crabs on burning Suaeda and tried to invent a solar desalination still using our shoes, John suddenly remembered we had cell phones.  The miracle of Verizon brought a nice man named Bill with a big truck to yank us out of our sandy Hell to explore and blog another day.

[Note—that isn’t really John’s car. His car isn’t that cool.  But we did get quagmired and rescued deep in the jungle.]

 

Taking a Shine to Varnishleaf

Varnishleaf

Dodonaea viscosa

Sapindaceae

Here’s a shrub for everyone, and I do mean everyone around the world. The shrub we call Varnishleaf in Florida must have a few names we can’t pronounce because its natural distribution ranges from here to Australia and back. Actually the other way around, since DNA research shows its origins to be Down Under. The international uses are as widespread as the cosmopolitan places, everything from making the hard wood into weapons to more medicinal applications than you can throw a pill at. In Florida we like this species as a tough drought tolerant landscape shrub with pretty fruits.

John and I did not go visit Australia to see Varnishleaf. There is plenty in the Hobe Sound National Wildlife Refuge cooking in the sun up on top of those sugar sand dunes.

Varnishleaf (by JB)

The puffy papery fruits resemble those of certain garden trees, especially Goldenrain Tree (Koelreuteria elegans) or Black Pearl (Harpullia arborea). Some readers will see “the same” fruit in species of Cardiospermum. The similar-pod list could expand, but why bother, the point is family similarities in these members of the Soapberry Family, the Sapindaceae.

Varnishleaf pods (by JB)

The predictable lists of “traditional medicinal uses” surrounding most common widespread bioactive plants can grow a little dubious and tiresome. Conduct a little research and you will find almost any plant you name to have served somewhere somehow to counter some common discomforts.

That cynical remark off my chest, a traditional use for Varnishleaf struck me as unique and particularly plausible: warming the naturally sticky leaves and applying them as a plaster over hurty places. Given evidence of antimicrobial activity, maybe sticky Dodonaea plasters actually help with healing. Free Salon Pas. Dodonaea seems to contain multiple bioactive contents, including saponins, cyanide, and more. Saponins are lathery-poisony compounds that put the soap in Soapberry. They are most famous as fish poisons.

Why would a shrub make shiny “varnished” leaves anyhow? Here we have a leaf with an array of adaptations for extreme sun. In Mexico Varnishleaf is a member of “Opuntia associations.” (Opuntias are Prickly Pear Cacti.) Come to think of it, right here in Florida Varnishleaf can be a member of the Opuntia association. This is a plant for blazing sun. So then an obvious guess about those ultra-shiny leaves is the same as mirrored sunglasses—to bounce away excess light and protect delicate tissues beneath. Seen microscopically, the top layer of the leaf has special varnish-making cells just beneath the surface. Plant ecologists Gary Brown and Bruno Mies commented on a related adaptation in the same species…the ability to orient the foliage vertically to minimize sun exposure. Also odd, the layer of photosynthetic cells near the leaf surface is thicker then in most leaves—a leaf designed for fun in the sun.

Varnishleaf leaf (by JB)

The fruits are showy and novel, whereas the flowers are merely novel. Apparently pollinated by wind, they have no petals, but rather many pollen-dispersing anthers, and extended pollen-catching stigmas.

The flowers—no petals, just the “business parts” (by JB)

Did you gulp at the idea of one species distributed from New Zealand to Hobe Sound? Varnishleaf has two outstanding abilities behind its wanderlust: 1. High salt tolerance. It can grow among mangroves. 2. The world’s toughest seeds. Experiments have shown high germination rates after 6 months in saltwater. Those little bitty seeds can float across vast oceans, perhaps sometimes within their capsules, and maybe sometimes aided by seed-eating migratory birds. Some of the seeds have an internal airspace.

Badass with Dodonaea-inspired shades (Photo not of or by JB)

 

Naked Embryos and Dead Man’s Fingers

Black Mangrove

Avicennia germinans

Verbenaceae

This week’s Friday field trip by John and George got nuked by a combination of work obligations, rain, and car trouble.  With reference to the last-mentioned, this post was written in the commodious Napleton Nissan/Kia Service lounge in Riviera Beach, with complimentary coffee and People Magazine.  So we’ll step back in time just a couple weeks.  Black Mangrove (Avicennia germinans) surprised us by practicing dispersal in massive quantities by bare naked embryos.  We found thousands of them in the tidal wash on the beach at the Hobe Sound Wildlife Refuge across the Intracoastal from Tiger Woods’s spread.  Everybody knows that flowering plants usually disperse as fruits or as seeds, but as exposed embryos?  In saltwater?  Yes.  And some were already rooting on shore, making it clear how you wind up with extensive stands of Black Mangrove.

Black Mangrove embryo castaways on the beach (photo by JB)

Googlization reveals this peculiarity to be old hat to mangrove cognoscenti, even being the basis for the specific epithet “germinans.”  But we’re nobody’s cognoscenti, thus our happy surprise at the little embryonic nudists.  It is also old hat to some plant propagators who soak Avicennia fruits to liberate the embryos for sowin’ and growin’.  By the way, the name Black Mangroves refers to the dark-colored wood.

Embryos from Avicennia species can remain viable over 6 months submerged in sea water and can float alive at least 50 km, although most dispersal is local.  The embryos are large, fleshy, and well provisioned before release.  They look like the innards from a giant lima bean.

Having escaped their fruits and seeds, and having enlarged, they  are in a sense prematurely germinated, and in this way vaguely resemble the precocious seedlings dropping from the unrelated Red Mangroves with a big prematurely sprouted embryonic root sticking out of the persistent fruit covering while still on the mama tree.

Inquiring minds may now ask, well, what about the third Musketeer,  White Mangrove?  Its fruits disperse in the traditional fashion—intact—but they have some “pregermination” going on too, as the seeds can sprout inside the fruits during dispersal.  This shared tendency is an interesting tidbit of convergent evolution where three different and unrelated species have all adopted premature germination, in different forms, to meet the challenge of saltwater-drift dispersal.

Dead man’s fingers (photo by JB)

Anyone with much experience hanging around docks has encountered spooky black gnarly “dead man’s fingers” rising vertically among Black Mangroves.    More convincingly than Bald Cypress “pseudo- pneumatophores,”   Black Mangrove pneumatophores have obvious adaptations as root snorkels.

The fingers are filled with spongy tissue suitable for gas exchange.  The finger lengths adjust to the need for air, and lenticels (breathing pores) on the fingers reportedly open and close in response to environmental conditions.