George Rogers

Bluegreen Algae, Cyanobacteria

Hey I’m no expert on cyanobacteria, but exploring nature, peeping through microscopes, and teaching botany, they crop up. Having the amazing ability to type words into Google and to read the results makes me a qualified Internet pundit! I self-declare a Ph.D. in cyanobacteriology.

Pundits love to define terms. Algae and so-called bluegreen “algae” are a point of vocabularial confusion apparently beyond the comprehension of newscasters. A complicating factor is that “algae” is a tough term to define, more descriptive of a lifestyle than of biological relationship. A grab bag of simply constructed non-flowering water-dwellers. That is a license to use a term loosely. Yet there is another way to see it. Bacteria are more crisply defined. Bacteria (and Archaea) are profoundly different from all other living things, right down to their basic biochemistry. For vocabulary lovers they are prokaryotes as opposed to the eukaryotic algae. The bluegreen “algae” are bacteria, cyanobacteria.

algae mat in canal

Cyanobacteria crop up in disparate contexts:

As symbionts, the main “botany classroom” role. Cyanobacteria are “good guys” as the right species in the right roles. Many cycads have “coralloid roots” poking aboveground looking pathological but actually inhabited by beneficial, symbiotic, photosynthetic, nitrogen-fixing cyanobacteria. (Nitrogen-fixers convert atmospheric nitrogen to “fertilizer.”) If you bust apart the floating fern Azolla…lots in South Florida…it has cyanobacteria folded into its leaves, making it a rice paddy fertilizer. Cyanobacteria can inhabit the traps of carnivorous bladderworts and turn up inside hollow-water-holding cells in sphagnum moss. The “alga” in some (cyano)lichens can be a cyanobacterium.
Nitrogen-fixing cyanobacteria living freely, or perhaps not completely free, in the dirt and in hydric soils bring nitrogen to the earth. During wet weather, great green globs of cyanobacteria jelly rise into prominence on the soil surface.
On wet surfaces. Sometimes before I powerwash the patio, it is interesting to scrape the stains and see under the microscope who it is: fungus? green alga? cyanobacteria? Often the last-mentioned looking like dark pain on concrete and stones.
In canals, lakes, and rivers. Summer in Florida, and “algae” in the news again! True algae, cyanobacteria, aquatic weeds, associated microbes and creatures, red tides, and dead zones are all part of the evil syndrome relating to our over-fertilized, over-nutrient-enriched, over-hyped Florida active adult lifestyle. We’re a wet state, not that these problems are unique to Florida, and natural aquatic systems did not evolve dealing with all the nitrogen, phosphorus, and other nutrients humanity puts in the water. Natural ecosystems evolved in a balance with “normal” nutrient levels, and when the levels skyrocket, some lifeforms suffer, while others benefit to the point of trouble.

Rising from the wet earth

Same as above, microscope view.

A windowsill experiment to see this is to put pondwater in four soda bottles. In one bottle put no fertilizer, and then increasing amounts in all the others. One drop in one, two drops in the next, and so forth. Wait a month. A harmful algal bloom right before your eyes!

eutrophication - Copy

How many sources of nutrient enrichment can you think of? Organic decay, sewage, septic systems, manure, biosolids, fertilizers. Twenty-some million Floridians and tourists generate oodles of sewage. Treatment does not remove all the nutrients, even passage through artificial wetlands. One way to shed nutrient-loaded sewage treatment water is as reclaimed irrigation water, inviting turf and ornamentals to take up the nutrients, and those nutrients are back into the ecosystem.

Agriculture comes up in the news about the polluted Lake Okeechobee system: manure, fertilizers, backpumping. And then there are biosolids, treated sewage sludge spread onto the earth.

As anyone who watches the news would know, releasing nutrient-enriched waters from Lake Okeechobee causes unwanted aquatic life where the water goes: unnatural weed infestations in the Everglades and harmful algal/cyanobacterial blooms along the rivers draining the lake, extending into the sea. That unwanted growth, especially the cyanobacteria “algae,” make dangerous toxins.

There are plenty of targets for the finger of blame, and authorities from whom to demand action. No need to repeat the usual list of suspects. I would not want to be any of them, because cures are not obvious, nor without downsides, and as Pogo croaks from the polluted swamp, the enemy is us. Florida was never meant to host a gazillion people.

Many stains on rocks and concrete are cyanobacteria.

Which sources of trouble can we control? Ample room for argument, but most controls will be tweaks, details, adjustments, NIMBY, and redirections. How do you diminish sewage nutrients, agriculture, and too much rain in Lake Okeechobee (restore more natural outflow?)? Curtail Florida development? Heresy! Seems to many observers, and recall my amateur status with no data, one actionable point might be limiting residential fertilizer applications, which might mean we don’t all need a big sprawling St. Augustine lawn.

Cyano-soup

It isn’t just the Lake Okeechobee system of course. This summer the eutrophic canals and ponds suddenly have smelly floating mats of green. Close examination of a floating mat is eye-opening. Tried it yesterday in a stagnant canal in Jupiter, speaking over over-development.

The mat from canal yesterday, dominated by Cyanobacteria (the striated filaments).

The mat is a tapestry dominated by filamentous cyanobacteria (marked by their cross-striations) interwoven with filamentous algae, varied single-celled algae and alga-like organisms, wriggling animalcules, and decaying globs of organic matter. Those decaying globs sink, stink, and take up oxygen as they go.

CLICK for a 40 second flyover.

One of the abundant filamentous ones is called Oscillatoria. It wiggles like some sort of mud-dwelling worm. CLICK to see the wiggle (about 40 seconds).

This may be an artifact of my limited experience, but that experience so far finds unicellular (sometimes clinging into clusters) cyanobacteria in the St. Lucie River, with the filamentous types (strings of rectangular or circular cells) in the floating mats on canals.

11 Comments

Posted by George Rogers on June 25, 2018 in Cyanobacterial Mats, Uncategorized

Tags: Blue Green Algae, Bluegreen Algae, Cyanobacteris, Eutrophic, Nostoc, Oscillatoria

Bedbug Seed is the State Wildflower

22 Jun

Tickseeds, Coreopsis

Coreopsis leavenworthii, and close relatives

(Coreopsis comes from Greek for bedbug, some species with bedbugish fruits. Dr. M. C. Leavenworth botanized in and near Florida.)

Asteraceae, the Aster Family

Today Jon and I worked on something we never work on…landscape species. Long story with no good natives photo ops. So in honor of garden species, here’s one horticulturists and wild plant enthusiasts both enjoy, as well as the State of Florida, making Coreopsis species the state wildflowers. There are over a dozen Tickseeds native in Florida, with two or three commonly encountered in our usual haunts.

Coreopsis gladiata, by John Bradford, above and below.

Coreopsis gladiata 3 - Copy

Species depend on interpretation. Coreopsis tinctoria beautifies most of North America and varies all over the map. The best interpretation of today’s C. leavenworthii, not my idea, is perhaps as a localized fringe element of that behemoth species. They can interbreed.

We can argue pointlessly about species status, but no sane person of taste and breeding would dare question the beauty of these little gems

C. leavenworthii…after the fruits fall away.

As with all members of the Aster Family, the “flower” is actually multitude, the big yellow “petals” being individual ray flowers. The dark center hosts a crowd of tiny dark purple disc flowers with orange stigmas, looking like the Clemson school colors.

Coreopsis stigmas

clemson0758

asteraceae

An Aster Family trait Coreopsis disc flowers display is the sexuality shifting from male to female. Stigmas rising from the lower reaches of the floral tube push yellow pollen to the surface of the flower head, starting it off male. As those orange stigmas continue to rise they surpass the pollen, making the flower functionally female.

Watch it…just a few seconds CLICK

The male phase, yellow pollen on the surface of the head.

Female phase. Pollen mostly gone, and the orange stigmas protruding.

Flip over the flower head. On the underside there’s a star of what look like sepals, but the points are the tips of specialized leaves (bracts).

Coreopsis backside - Copy

As the head transforms from flowers into a cluster of micro-fruits, those bract tips curl up to form a cup protecting the seedlike fruits. The fruit bowl looks at first glance like a spherical bud.

This “bud” is made of the bract tips seen in the photo just above, now in the fruiting phase. They curl up together to form a cup around the little fruits.

The fruits give the name tickseed. They’re paper-flat, and have two tiny horns it seems to help it cling to passing creatures. Around the perimeter is a narrow wing mayb for fluttering if hte horns don’t snag transport.

Fruit cup opened to show winged bedbug fruit, and some flowers in female phase at top right.

Sleep tight.

6 Comments

Posted by George Rogers on June 22, 2018 in Coreopsis, Uncategorized

Tags: Coreopsis, Tickseed

Sawgrass and the Crocodilians

15 Jun

Cladium jamaicense

(Cladium means “branched,” referring to the flower cluster. This species vacations in Jamaica.)

Cyperaceae, the Sedge Family

John is busy today relocating, locally, so I’m on my own, in Pine Glades Natural Area near Jupiter, Florida.

What plant is most emblematic of Florida? Well, yea okay, “palm tree,” or “Hibiscus,” but after that, dangit, sawgrass. It appeared in the blog a few years ago, but nobody would recall, and it is in bloom now, so here is a revisit. Misnomer alert, sawgrass is a sedge not a grass, but, after all, Pond Hawks are not birds.

Pine Glades

Now that we’ve got that straight, sawgrass is the dominant marsh plant of the Everglades. Such a keystone species has been the object of much study, and a tidbit from research is that sawgrass’s ability to dominate does not come from being the biggest nutrient-sucking bully in the mud, but rather, the opposite. It competes on its ability to thrive on less in naturally nutrient-poor environments, perhaps even curtailed by too much P.

Rain rain rain

Everglades waters experience nutrient pollution from points north, especially phosphorus. Unlike sawgrass, competing plants use the phosphorus enrichment to achieve great vigor, examples of the interlopers including cattails, dollarweeds, hempvines, and others. And to make it worse, cattails are less fussy than sawgrass about unnatural water fluctuations.

The stalks in the female stigma phase are the white ones.

Sawgrass is not limited to the Everglades. There is plenty around Palm Beach County and points northward, although generally in mixed mosaics with other marsh dwellers. The overall range is from South America to Virginia. A similar species lives in the western states, as well as a smaller cousin (Cladium mariscoides) from Florida to Canada.

What’s the most famous thing about sawgrass? The sawtooth leaves of course, not that serrations are unique to this species. It’s the Saw King, however. You have to feel sorry for chain gang escapees chased by bloodhounds into the Everglades. I know the painful experience from recreational botanizing, let alone from draining the swamp. Odd coincidence that Hamilton Disston the drainage conqueror of the sawgrass Everglades was a Saw King himself, coming from the Disston (Saw Company) family.

disston saw

Cladium teeth

The serrations angle forward. Why do they exist? I don’t know. The kneejerk answer is protection from herbivores, or from larger critters crashing through. My gut says “phooey.” When thinking about leaf structure, the mental checklist should cover water, light, and wind, and again, gut says “forget that.” The answer I like, from earlier botanists, is vine severance. Take a walk in a marsh: vines everywhere on everything. But not sawgrass, it is pristine and vineless. Any vine braving those wind-slashed Ginsu knives would shred. An experiment to try.

The flowers are pretty and have an odd feature. Sedge flowers tend to mature their female pollen-receiving stigmas before the male pollen-producing stamens. In a sawgrass an entire stem tends to have its flowers at the same phase, okay fine. Contrary to the usual sedge female-first pattern, however, the flowering stems start out mostly male, then go almost 100% female, and then wind up mostly male again mixed with maturing fruits. They switch predominant sex twice: maleish, femaleish, maleish.

Are those mostly-male-first stems violating the ladies-first rule? (The proper term is protogyny, pro-TOJ-en-ee.) Not really, the flowers actually do start out female, but it all goes awry in an odd turn of events. The flowers are in pairs, with one member of the pair older (or more developed). The older member starts developing female-first like a good sedge, but most of these flowers have their female units stop developing while the male stamens proceed to maturity, giving the stem a predominantly male-first outcome. The stalk changes its mind.

Female phase…fuzzy white stigmas

The percentage of females aborting might be highly variable or sensitive to environmental influences. There’s room for study.

After all that, the younger members of the flower pairs mature their female stigmas with no mishaps, allowing the stalks to switch to mainly female phase, looking pale from the distance covered with white stigmas.

And finally then, after the female phase begins developing fruits, the male phase of the younger flowers arrives, with the grand finale being functionally male flowers mixed with maturing fruits.

Female phase dwindling, a male anther (brown) rising.

Having one sex mature before the other is common in wind pollinated plants, promoting cross pollination and minimizing self-pollination. So female-first sedges are no big whoop. It may be mere ignorance, but I can’t think of any other triphasic plants. The book-end male phases would keep pollen in the air through the population’s entire flowering and early fruiting season, while still minimizing self-pollination.

Sawgrass reproduces clonally by rhizomes, as do most marsh plants. So then, what is the role of that complex sexual pollination cycle? To allow seed dispersal to new establishment opportunities? Sure, and studies have shown even within a marsh blanketed with sawgrass multiple genetically separate individuals can be interlaced. In a marsh where sawgrass clumps mix with competing species, the seed-grown clumps are potentially each distinct genetic experiments in the competitive context. Survival of the fittest to then spread by rhizome…and to make more seeds.

The seedlike fruits (called achenes, AY-keens) are a little puffy, probably for flotation. Do animals help with dispersal, externally or internally? Bird dispersal is fair to presume, and the achenes have the roughened surfaces typical of small wetland fruits and seeds, speculatively there to cling to moist and muddy creatures. But take a guess who else may be influential in matters of the marsh ? Wildlife biologist S.G. Platt and collaborators in 2013 documented plant dispersal by crocodilians, and found sawgrass fruits among the mix in alligator fecal matter. That’s the way to conquer the marsh! Pre-fertilized, naturally acid treated, and relocated by armored carrier.

…………….

To dig deeper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4240397/pdf/mcf197.pdf

5 Comments

Posted by George Rogers on June 15, 2018 in Sawgrass Revisited, Uncategorized

Zebra Longwing Butterflies

08 Jun

Stuck home waiting for a repair visit. John is homebound as well. Might as well put the trapped time to good use with backyard nature, the feature attraction being zebra longwing butterflies dancing on the firebush.

Firebush. Zebra longwings lovin’ it!

Being our lovely state butterfly, this species is about as abundant on the internet as it is in my weedy so-called yard this morning, so we’ll attempt to cruise past the ubiquitous info on better web sites than this, and delve into some eclectic funny business.

Just a guess, but Bidens exposes pollen aplenty. Perhaps this stop is for pollen.

Zebra longwings are part of the large warm-climate butterfly genus, Heliconius where most species have coloration different from ours, although the related Heliconius peruvianus in Peru and Ecuador is almost identical. The Zebra longwing ranges from rubbing shoulders with H. peruvianus up through Texas and Florida, migrating sporadically into the central U.S., knocked back southward by Jack Frost.

The striking color pattern is probably best interpretable as “danger don’t eat me” warning coloration. Beautiful, yet treacherous with cyanide-related poisons. I’m not sure what percent of the toxicity comes from the host plant as opposed to what the adult manufactures, probably substantially the latter. There is second way to interpret the color pattern, but hold that thought a moment. Two functions for one pattern are possible.

The black and white bristly caterpillars can denude their host passionvines, defeating the plant’s protective hairs. The larvae bite off the hair tips, and weave a protective silk mat over the defenses.

The adult food plants are diverse, and the longwings love firebush. Zebra longwings and close relatives are the only butterflies known to consume pollen in addition to nectar, diversifying their salad bar. For pollen, they like members of the squash family, although I do not know if that preference shows up in Florida. The pollen protein extends their lifespan beyond most other butterflies, and boosts their reproductive capacity. Further, it probably provides raw materials for manufacturing those cyanide-based poisons.

Zebra longwings are among the pollinators known as trap-liners, able to remember a recurring feeding route. They circle home to the same roosting sites at night to cluster for protection from predators. What protection comes from a butterfly gang? Not very scary after all. Hmmm. Here is a thought: Zebras, the hooved mammals, obviously have similar striping, but not as a poison warning. They probably taste dandy to a lion. The zebra stripe protection comes from confusing big kitties by obscuring the outlines of single individuals in the herd. When zebra longwings roost in crowds like a herd of zebras, do their “zebra” markings render angry birds unable to single out individual victims?

CLICK for zebra op art

Same going on here? CLICK

After squabbles for dibs, males mate with the females while the females are still in their pupa or as they emerge. The boys are drawn to the larval mating area partly by chemicals released by caterpillar damage to the host plants. The male gifts the female with a cyanide-laced bomb (in the spermatophore) to defend the female and the brood, and leaves an “antiaphrodesiac” chemical to signal other males to flutter off. The lepidopteran equivalent of a wedding ring.

Ever sense you don’t see as many or as diverse butterflies like you once did? Maybe your memory has gilded your childhood, or then again it might have something to do with pesticides, or extreme herbicidal weed control. Aerial spraying of insecticides, chiefly the insecticide Naled to counter mosquito-borne viral diseases, is harsh on butterflies, controversially in Miami-Dade. Naled is a chlorinated organophosphate related to the now-banned insecticides Dursban and Diazinon, and also to the genocidal gas Sarin. (Gratuitous inclusion of scary tie-in.) How much do we fear Zika and West Nile? How dangerous is Naled to butterflies and to children? How much protection does Naled spewed from airplanes provide? What alternatives exist? All that is beyond the scope of our happy little blog. Yet food for thought, butterfly-lovers.

CLICK to feel sick.

What bugs me abut butterflies is how they manage to fly. Looking out the window right now, it looks like the wing is a firm paddle flapping up and down. But that couldn’t work— they’d just bang against the ground. Must be more to it. Biologists and photographers have studied butterfly aerodynamics, and the Google take-home is that the wing motion is intricate, although too quick to see…another example of the bewildering complexity of simple life forms. The wings twist, turn, distort, curve, curl, and glide like the adjustments of a helicopter blade, or of a swimmer’s hands, although fancier and more dynamic. I set my camera to “video,” filmed the flight, and slowed it down to try to catch some action. The result is below, please click on the link. Among myriad variations, prominent wing movements appear to be reaching forward, then cupping downward and pulling back, subtly resembling a swimmer doing the butterfly stroke. How does a noggin smaller than a pinhead compute all that coordination?

CLICK HERE and see if you can interpret the butterfly flap

Here is what I think….judge for yourself.

———————————————————————

Music in video: Ryan Andersen Happy Life

11 Comments

Posted by George Rogers on June 8, 2018 in Uncategorized, Zebra longwing

Tags: Heliconius, Zebra longwing

Cat-Tails Twistin’ and Chillin’ in the Wind

25 May

Typha latifolia and T. domingensis

(Typhos is Greek for marsh and is an ancient name for these plants, latifolia means broad leaves, and domingensis means lives in Dominica.)

Typhaceae

Cat-tails by John Bradford

Fuzzy corn dogs on vertical skewers. Cat-tails we all know—big, abundant, curious-looking. John and I photographed today in the Haney Creek Natural Area near Jensen Beach, Florida where the cat-tails were twirling in the breeze. Two native species share Florida:

Typha latifolia has a huge distribution, in the U.S. from Florida to Alaska, and far beyond. Its male and female flowers are distinctively adjacent on the spike. The seedlike fruits burst in water.
Typha domingensis likewise has a broad distribution, on average preferring warmer places, and often in brackish water. This species has narrower leaves, and the male and female flowers have space between them on the spike. Its fruits don’t rupture in the drink.

Typha flower spikes sometimes have developmental abnormalities, such as two clusters of female flowers where there should be one, or stalks with male flowers only. Our two species hybridize, and the oddities could conceivably be due to genetic mixing. The hybrids can have orange spikes.

Deformed spike

Countless historical uses for cat-tails range from medicines to weaving and thatch. Miami botanist Julia Morton in 1974 listed hundreds of uses (see link 1 below). The rhizomes are food, including “Cossack Asparagus” in Russia, although local authors warn against consumption due to yuk accumulation.

What I like are the millions of fluffy windblown seedlike fruits. Soaked in kerosene, the puffy spikes become torches, and the flammable seeds once gave dramatic theater lighting effects. The pillowy masses stuff anything that needs to be soft or buoyant such as lifejackets during WWII, and even baseballs and cradle linings.

By JB. Look to the left.

Cat-tails love nutrients to a fault. As waters become enriched with pollutant nutrients, most famously phosphorus, cat-tails expand and displace other communities. They sometimes form extensive monocultures interlaced with rhizomes that start growing shortly after seed germination. Typha domingensis has a positive role in stormwater treatment areas removing phosphorus pollution, yet a negative role as a pollution-fed invader degrading the Everglades.

Pure CT stand. Leaves brown.

Now for the cool part—

The leaves come up arranged in a fan, and twist artistically in unison as the blades grow upward.

Leaf blades twisted, and with blue sunscreen.

Why grow twisted? Optimal positioning for photosynthesis? Botanists have been pondering that question for a long time, sometimes in engineering detail. Biophysicists Zi-Long Zhao, Zong-Yuan Liu, and Xi-Qiao Feng recently (2016) took a deep stab at it (link 3 below.) Their study rests on the observation that the twisted leaves twirl in the wind like those twisted front porch wind-spinners.

We can see it happen: CLICK FOR SHORT VIDEO TAKEN THIS WEEK

The biophysicists determined the twisted twirling to serve two functions:

1. To reduce wind-drag on the plants making damage less likely, and 2. To reduce wind-induced vibrations.

Now do not get me wrong, I’m not questioning their elegant analyses and hard-science conclusions, yet forgive me for tossing in a speculative add-on with no data:

Many leaves, especially in wide open hot places, experience too much solar exposure, suffering direct sun damage, interference with photosynthesis, and excessive heat. Many tropical species of open sunny areas have a special mechanism called C4 photosynthesis to protect their photosynthetic production from the blazing sun. Cat-tails do not have this mechanism despite sharing hot sunny haunts with C4-equipped competitors.

Cat-tails thus may need some tricks of their own. The blue waxy covering on Typha latifolia can be interpreted as sunscreen. When the leaves twirl, no single surface experiences direct sun exposure continuously. Instead the rays distribute evenly on both sides of the blade. Moreover, the natural spinning fan blades probably shed heat directly and by evaporative cooling. Have you ever seen a sling psychrometer used for measuring relative humidity? It works by twirling in the air a thermometer surrounded by moist wrapping. Its evaporative cooling rate relative to a dry thermometer measures humidity. Twirling and evaporating likewise, the Cat-tail leaf is a living sling psychrometer perhaps.

Relevant links:

Botanist Julia Morton and a million uses for cat-tails: CLICK
Cat-tail weaving: CLICK
Reference for Typha leaf twisting: CLICK
Sling psychrometer: CLICK

Pat Bowman after the blog appeared sent this cool video of the seed release. Stand back and CLICK

5 Comments

Posted by George Rogers on May 25, 2018 in Cat-tails, Uncategorized

Tags: Cat-tails, Cattails, typha

DOLLARWEED

18 May

Hydrocotyle umbellata (and several close relatives in Florida)

(Hydrocotyle means water plate. An umbel is the type of flower cluster shown below.)

Araliaceae (Apiaceae)

Dollarweed Flowers by John Bradford

Dollarweed today…a monoculture, with floating rhizomes.

John and I worked today at Haney Creek Natural Area. A million bucks worth of Dollarweed there. Did you know it is native?

To help out today I’ve invited a lawn specialist, Dr. Hoppy Lubber, who agreed toshare 5 minutes of his precious time.

CLICK HERE

3 Comments

Posted by George Rogers on May 18, 2018 in Dollarweed, Uncategorized

Tags: hydrocotyle

Air-Potato Yam

11 May

Dioscorea bulbifera

(Dioscorea honors ancient Greek physician Dioscorides. Bulbifera manes “bears bulbs.”)

Dioscoreaceae

What’s the difference between a Sweet Potato and a Yam? Answer below.

Today was pleasingly a “normal botany Friday” under hot sun after too many weeks with distractions in John’s affairs and mine, more disruptions to come. We worked today on a photo project at the Haney Creek Natural Area near Jensen Beach, Florida.

Air-Potato Yam there is a super-vine rising over six inches per diem bullying other vegetation all the way. For yam-lovers that sounds like a top crop, but truth be told, the underground tuber is small and bitter to toxic. The stem-borne tubers (bulbils) resemble potatoes in appearance, but again, not lunch.

Overhard spud. By John Bradford.

A superior yam producer is a very similar likewise local invader, the Winged Yam, Dioscorea alata, different most notably by having a 4-angled or winged stem (vs. round), a bigger better underground yam, and smaller aboveground tubers.

Now back we go to Air-Potato. Its tough, durable, nasty yams provide an old explanation of how it came to tropical America, as ship-board grub, maybe on slave ships. The cruise chefs were not picky. Confounding this old notion, however, are recent DNA studies showing Chinese ancestry for Florida populations. Multiple arrivals are likely. Apparently the USDA, sparked by introduction-king David Fairchild, deliberately introduced Air Potato into Florida. Rockstar horticulturist Henry Nehrling possessed the cursed vine by 1905, noting even then its aggressive demeanor.

In yam leaves all the main veins converge at the notch. By JB.

As with other “edible” species, some cultivated air-potatoes are non-toxic or minimally risky with correct preparation, whereas other strains can be dangerous, in this case with toxic compounds so similar to human steroids they have been used in making pharmaceuticals. The first birth control pills came from yam steroids.

This “potato” had dropped to the ground. Looks like once there, it means business! Taken today.

Whatever its edibility vs. toxicity, the plant has ancient history in food and medicine, especially in the Old World tropics, where it evidently originated, although where it is “native” is vague because humans moved it around even in ancient times. The recorded historical medicinal uses would fill a page. You name it. I don’t even know what some of those old ailments are.

When a plant invades, a common course of combat is to seek its natural enemy in the invader’s homeland. The enemy of my enemy is my friend. True of Air-Potato, with the deliberately introduced leaf eating beetle Lilioceris cheni, which I hope remains our friend.

An obvious concern is the hit-beetle might expand its lethal ravages to native species, in the present case most notably Florida native yams. Nobody would be dumb enough to unleash the destructors without testing their disinterest in the good species. But, for neurotics like me, there remains the dubious doubt of potential change of tastes. Such pest-of-the-pest introductions have run out of control before. I think of it pessimistically this way…many weeds and insects have evolved immunity to pesticides; it is commonplace, so why couldn’t some little enzymatic mutation allow the beetles to start munching non-target species? And how effective are the beetles at controlling the naughty vine to begin with? Skeptics are such nuisances.

Dioscorea bulbifera leaf lineup

I’ve no recollection of Potato-Vine in flower despite many field outings with my wife Donna’s ecology classes to examine it among other invasive exotics. There are separate male (pollen) and female (seed) individuals. To the best of my Googling, male flowers seem to be unknown in Florida, and females rare.

Sweet Potatoes vs. Yams. I love both! A sweet potato is in the morning glory family, and is a root. A yam is unrelated, in a family among the monocots, with the edible part being a tuber, that is, a fleshy underground stem, or one of those air-borne bulbils.

Fiddle-Leaf Dock

04 May

Rumex pulcher

(Rumex comes from Latin rumo, to suck, because ancient peoples sucked the leaves to relieve thirst, see below. Pulcher means pretty.)

Polygonaceae

Today splendidly in flower in a weedy meadow…I love weedy meadows!…was a locally rare treat called Fiddle-Leaf Dock.

Leaf looks a liddle like a fiddle if you see the resemblance.

It is one of 200 species of Docks enhancing most of the temperate world. Like many Docks, today’s species is native to Europe and probably Asia, where plants of this genus are players in human affairs all the way back to that sucking mentioned above. Docks are often called Sorrels, which is a flavor designation, not a botanical classification. Sorrels tend to contain oxalic acid, giving them a “refreshing” acidy sour taste people still use for a quick pick-me-up. I used to enjoy red Sorrel beverage in Barbados sweetened with Barbados sugar, or with rum if you prefer. Various Sorrels fall into divergent botanical groups, including Hibiscus, Oxalis, and Rumex sharing possession of oxalic acid or similar flavoring. All this being so, Docks have long had a place in the kitchen and herb garden, where some cultivated species can be as pretty as they are tasty.

Taken today…pretty reddish tones.

Oxalic acid, even if refreshing in small doses, is bad for you in many ways, so please do not eat the weeds. Species of Rumex contain also sometimes ascorbic acid, Vitamin C, preventing knaves from becoming scurvy knaves.

Rumex pulcher plant 1

Turning abruptly now to biology, species of Rumex have a particularly curious feature. The fruit is a small seedlike unit called an achene (AY-keen). Upon ripening it remains embraced in three persistent flower petals (technically, tepals) serving as protective walls encasing the fruit. Now for the weird part, either one or all three of these petals experience massive thickening of their mid vein into a thick glossy green, bright white, or red balloon called the tubercle. “Miss Kent” in The Magazine of Natural History described it well back in 1830:

The whole genus Rumex may appear strange at first sight on account of a tubercle (in some species very large) which destroys the outline of the flower. Some of these tubercles appear like little rubies, and add much to the beauty of the flowers.

Remember, the fancy tubercle is on the “petals” surrounding a tiny fruit, but why? No single answer, but first of all, the tubercle like a ruby is eye catching. In Fiddle-Leaf Dock it is showy too, bright white rather than ruby.

Wacky fruiting units with the big white tubercles destroying the outline of the flower. The fruit is hidden behind the tubercle-bearing petal.

It probably attracts birds, which for sure eat red or white berries and seeds. “Grain-eating” birds are reported dispersal agents for Rumex. Isn’t it convenient that the unit the birds sees and perhaps crunches is not the fruit itself, but rather a false grain on the protective cover? The actual tiny non-showy fruit presumably sneaks along for the ride achieving avian dispersal in one piece. And there’s more:

Multiple botanists have documented an odd correlation between Rumex tubercle size and proximity to the sea. Noticed too many times in too many places by too many observers to ignore. Large-tubercle species tend to be coastal, and far more interestingly, within single species bigger tubercles near the sandy shores and lesser ones inland. That leads to the obvious suspicion of tubercles aiding sea dispersal as floats and as bumpers on abrasive sands.

If the oceanic adaptations are “the” function, why do inland species have tubercles at all? And why gorgeous little rubies and shiny white gems? I’ll guess the tubercles probably started out serving variably as bird-bait as well as floats and bumpers, with those latter two functions gaining prominence in maritime habitats. You know, sort of pre-disposed.

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Posted by George Rogers on May 4, 2018 in Fiddle-Leaf Dock, Uncategorized

Three Petal Bedstraw…might curdle yer cheese and stain yer bones

23 Mar

Galium tinctorium

(Galium comes from Greek gala, for milk, because the plants have an ancient history for curdling milk, tinctorium means used for dye.)

Rubiaceae (Coffee Family) (Art by Heather Calderon)

Galium obovatum by John Bradford

John and I worked on weeds in Halpatioke Park today near Stuart, Florida. How many species of weeds compete within a 100 yard square? Bedstraws, species of Galium, are little weedy charmers in the Coffee Family with good looks, nice aromas, and historic roles in human affairs. Galium is a huge worldwide genus, about 600 species.

Galium tinctorium by JB

Today’s species ranges essentially from the Arctic Circle through Florida to the tropics. It likes low wet grassy places.

Galium flower small

If you read the explanation of name above, you can stop reading now, as that is the story. But if choose to proceed, let’s start with the milk thing. Vegetarians watch what cheeses they eat, or should, because most rennets (enzymes used to curdle milk proteins into cheeses) come from the fourth stomach of unweaned calves. For those who want none of that, there are chymosin “fermentation” rennets using calf genes genetically engineered into microbes. Behind door number three are vegetable and microbial rennets dating back into antiquity, and Galiums are among these. Even better, Galiums do not merely harden cheese, but they also color it ever so tempting. (See their next set of useful attributes.)

Galium rennet

Before that, however, a question: Why would a plant develop the ability to coagulate animal proeins? My guess is to deter herbivory, and that calls for an experiment. Excuse me while I go fetch a piece of bedstraw to micro-nibble. (Result below)

Red pigment in the weird fruits.

Bedstraws have a second set of ancient uses in addition to stuffing mattresses and making cheese. Civilizations around the world use them as dyes. They are very closely related to the madder dyes, and have quite a history of their own. The lower portions of the plants and the roots yield a red or yellow dye.

Red pigment in plant base.

And that brings us to the final unwise use. Please do not eat the weeds. People have some history of eating some Galiums under certain circumstances. I’ll say boringly that the plant is loaded with bioactive principles. And far more interestingly, there is a report that eating Galium dyes the bones red. I have no idea if that is so, but….. Galium textbox 1

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Posted by George Rogers on March 23, 2018 in Bedstraw, Uncategorized

Tags: Bedstraw, Galium, Halpatioke

Southern Needleleaf (revisited)

16 Mar

Tillandsia setacea

Bromeliaceae (Pineapple Family)

Tree of Tears

Live Oak – Quercus virginiana

Fagaceae

Today John had obligations so I did something botanical I enjoy near my home, perpetual exploration of Riverbend Park on the Loxahatchee River west of Jupiter, Florida, living proof you do not need to go far for good times with Mother Nature.

Riverbend Park and the contiguous Loxahatchee River Battlefield Park, in these paragraphs jointly called “the park,” is the site of the two-phased 1838 Battle of the Loxahatchee where 1500 U.S. troops killed an unknown number of indigenous people to make room for St. Augustine grass lawns.

A park icon is the “Tree of Tears,” an old Live Oak in poor condition, where the Seminoles allegedly sheltered their battle dead and dying. The historical connection between that specific tree and the battle history might be a little tenuous in a “scientific sense,” and it seems tacky for a modern author selling a book to dub the tree the “Tree of Tears.” Apparently the Seminoles did not bestow the name on their tree.

Tree of Tears

Whatever its true history, the tree is a big gnarly old Oak among similar old gnarly Oak neighbors in the close company of likewise large Bald Cypresses and Water Hickories. A magical, and noisy, place with a drumline of three woodpecker species.

Southern Needleleaf on or near Tree of Tears

The massive Oaks are home to literally thousands of epiphytes representing numerous species, with by far the dominant one being Southern Needleleaf, Tillandsia setacea, a Bromeliad relative of Spanish-Moss, Ball-Moss, Cardinal-Airplant, and several others. The Southern Needleleaf clusters can occupy the old (and sometimes young) Live Oaks lined up along the branches so numerously the tree looks like a Pine, since the epiphyte’s leaves are the size and shape of pine needles, although usually with a reddish cast. This species has entered the blog before, and I feel moved to a redo.

Southern Needleleaf can occupy different host species, but in my experience around here it has a powerful predilection for Live Oaks. Vigorously growing Live Oaks can sustain countess Southern Needleleafs which seem to shun the adjacent Bald Cypress and have little love for the Water Hickories. Interesting pattern—Why?

Could it be the Oak leaves? Let me explain. Epiphytes share a problem: they are rooted high, dry, and nutritionally deprived up on tree branches. No roots in the earth. They each have their own fascinating special tricks for coping within treetop living. Tillandsias in general, including today’s species, have a covering of umbrella-shaped scales on the leaves able to absorb water and nutrients in the water.

Southern Needleleaf basal covering of absorptive scales.

The scales magnified.

Southern Needleleaf has its umbrella-shaped scales concentrated at the bases of the long spindly leaves. That is exactly the same place the leaf cluster functions as a trashbasket capturing fallen Oak leaves and other debris, including possibly insect frass. (Frass from insects…suggesting symbiosis? Ohhhh, that’s pushing things a little too far for the moment.)

Southern Needleleaf catches debris in its trashbasket at the same level as the heavy covering of scales.

The leaf blades have the upper-inner edges rolled into a vertical groove, especially at the leaf base trashbasket zone. Picture a drinking straw slit along one edge. The grove is perfect for catching water and organic debris, which is present and sometimes stuck to the scales inside the groove.

The groove at the inner-upper side of the leaf base.

Now, of course there are no data, no proof, but those scales and that groove at the debris-catching level look to me like this plant’s pantry.

Microscope view inside the groove, with trapped compost stuck to the scales.

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Posted by George Rogers on March 16, 2018 in Southern Needleleaf revisited, Uncategorized

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