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Florida-Rosemary

Ceratiola ericoides

Ericaceae

 

The local white sand scrub was at its best today, sunny yet cool, with fresh growth and flowers, including white Innocence (Houstonia procumbens) and Sky Blue Lupine (Lupinus diffusus).    Although not near its peak, also with flowers was Florida-rosemary, a curious shrub.

Is it related to culinary rosemary? No

Does it smell like kitchen rosemary, no not at all, contrary to assertions all over the Internet.   (Here we have a great example of how BS can spread on the Internet.)

So why is the Florida species called rosemary?  A superficial resemblance, convergent evolution.

Ceratiola ericoides 5 far

Florida-rosemary.  All photos today (except halo) by John Bradford.

To my eye, Florida rosemary looks more like a conifer than a Mediterranean herb.  Its leaves are stiff, thick little “needles” arranged stiffly on vertical branches.  The little succulent leaves are an adaptation for life in the highest driest most exposed white (or occasionally yellow) sand scrub soils.   Deserts evolve succulents and needle-leaved plants, so hereya go.

ceratiola druits

Leaves and fruits (not today)

If you survive on high, super-drained, nutrient-poor sugar sand, is it better to have deep penetrating vertical roots to drill down to wetter layers, or to have widespread shallow horizontal roots?    Depends, I guess.   Saw palmetto has such deep roots they have “air pipes” built in.    Rosemary goes the opposite direction, its roots splayed out horizontally like an octopus on ice.   A little erosion exposes them.

ceratiola roots

Lotsa shallow roots

 

Having a moat of your own shallow roots has advantages.  Obviously you catch every drop of water and maybe even nutrient-bringing dust, debris, and rainwash as it arrives.    And there’s more:

Florida rosemary is one of the more famous allelopathic plants known to botany.  Allelopathy is the ability to poison the competition directly, or indirectly by interfering with microbes or nutrient availability.  Those roots undermining potential competitors undoubtedly help spread the chemical warfare.

Ceratiola chemistry is complex, and no doubt there’s still much to discover.   One of the more intriguing tricks up its sleeve is production of a compound called ceratiolin.   In the presence of light (stay tuned on that) ceratiolin transforms into a natural herbicide called hydrocinnamic acid.  Researchers have shown rosemary extracts to prevent germination or early growth of its frenemies, and rosemary in scrub enjoys splendid isolation, with a vegetation-free “halo” around the base.

Ceratiola halo

Keep out!   The rosemary on the right has a vegetation-free zone around the base.

Recently, biologist Cody Gale and colalborators related the nocturnal habits of the Rosemary Grasshopper (Schistocera ceratiola) to ceratiolin.   It seems if the grasshopper is out by day, the ceratiolin it ingests would turn by light exposure to hydrocinnamic acid, giving the buggie a tummyache.   I have a weird small-world personal connection to this insect.  One of the co-discoverers of the hopper in 1928, Theodore Hubbell, was a personal friend of my grandfather’s, who lived in Florida.   As Hubbell said, “Finding a new bug in the Florida scrub … gives me as much thrill as a hunter gets from bagging a deer.”

The grasshopper lives its life exclusively on Florida-rosemary, when young camouflaged as a rosemary leaf, and when older, camouflaged as the stem.  Check it out, by clicking here.

The grasshopper is not the only exclusive insect.  Also restricted to Florida rosemary is its own Leafhopper (Alconeura bisagittata), and a deeper curiosity, a small bug (Hemipteran) known as Keltonia balli.  It lives its simple life on the male flowers, eating the pollen. (The plants are separate male and female with the flowers small and non-showy.)

ceratiola male

The male flowers, how it looked today

Walking the scrub on a hot day presents a pleasant aroma, which I’m pretty sure comes from the rosemary.  Chemists have not ignored it.  The part that gets me wondering is why the aromatic volatilizations differ substantially seasonally.   If generalized reports of wind pollination with no pollinators to attract are accurate, could the seasonal emissions have to do with repelling pests?    Or, to stretch uncomfortably, with inter-plant signaling? That phenomenon is known.

I’d be scratching my head trying to think of another local plant with three insects all its own.

 
4 Comments

Posted by on February 6, 2016 in Florida-Rosemary, Uncategorized

 

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Forked Bluecurls

Trichostema dichotomum

Lamiaceae

John and George took to the scrub today in Seabranch State Park near Hobe Sound, Florida.  Sunny but nippy The recent rains have made the lichens soft, the spiders hide, and scrub plants grow new “spring” basal growth.    The only two species showy-flowery today were American Nailwort and Bluecurls.   Both are pretty little curiosities.  The Bluecurls is showier, so it gets to glory.

tricho protruding stigmas

Bluecurls.  The style (longest unit in the curled cluster, shaped like a fish hook, upper right) greets the bee first. All photos today by John Bradford.

Handbooks generally describe Forked Bluecurls as annual, and no doubt it is often, but possibly not the whole story.    Today new growth was rising around the bases of last year’s stems, growing from deep taproots, making the plants at least in today’s experience what I’d call scrub perennials, several species there behaving identically.  Forked Bluecurls seems remarkably lightly studied, given its good looks.    Most Trichostema species live in the arid West, and have received more attention there.  So now hear this:  today is interpretative and based on the botany of other Trichostema species.    This is my speculative extrapolated “take,” not established fact.

Beyond the coloration, the outstanding attribute is a set of long curled (pollen-making) stamens and one  longer (pollen-receiving) style reaching out the front door of the flower.   The outreach may seem an obvious adaptation to dust  pollen on the back of a bee, but there’s more to think about.    First of all, why the bee’s back?   The bee does not have a back-scratcher, and can’t remove the pollen burden.

And why the long down-curled configuration?   Here is how an observer in the 19th Century described the similar flowers in California Trichostemas:

Trichostema Meehan

See the bee CLICK (on similar California Trichostema)

Early when the flower is open, the stigma (pollen-receiving organ) sticks out just a little more than the stamens.    Makes sense—pick up incoming pollen from the arriving bee before depositing new grains on it.  True of many flowers. Okay then.

But as the flower ages, the stamens and style continue curling inward into a position where bee-pollination can’t happen.  Self-pollination has been reported in our local species and in other Trichostemas.   I think, and this parallels many other plants, the severe incurling represents a back-up mechanism, plan B, self-pollination after giving the bees first dibs.

tricho leverage

The calyx (green cup below the blue petals) has the back edge raised.  The flower can bend to greet the bee but it can’t bend back.

Trichostema is an appealing mint, complete with a pleasing minty fragrance to the fuzzy-sticky leaves.   Some mints share a trick with likewise strongly bilateral orchids…twisting their flowers 180 degrees, called resupination.   The Bluecurls flower looks like an orchid  (or vice versa if you are not an orchid chauvinist). Trichostema twists in an unusual way with apparent unusual “purpose.”

The calyx (small green cup around the base of the flower) has five triangular lobes on its rim:  three together and long, and two together and short.   (In most mints the three long are on the floor side of the horizontal calyx and the two shorter ones at the roof side.)

When the blossom is at its early peak for pollination it stands nearly vertical.  The three long calyx lobes stand behind the blossom as the bee approaches, forcing the blossom and the curling sex organs to bend forward onto the bee as it rests on the dotted landing-lip.    Those three tall lobes, like fingers behind a basketball in a freethrow force the action forward.

tricho late marked

Late flowers.   The stamens and styles are curled into an embrace, presumed self-pollination.    The calyx in the red circle recently lost its petals; the three long calyx lobes remain erect in back.  The older calyx in the yellow circle has the three lobes now repositioned into the diving board position with the seeds about to take the leap.

Then their role and position changes.    After pollination, the blue petals drop away leaving the calyx containing four “seeds” (nutlets).   To keep these from falling out prematurely, and to give them a springboard (almost literally) at the right time, perhaps when a raindrop strikes, the cupular calyx twists 180 degrees relocating the three long calyx lobes to the doormat position and the two short lobes as an awning over the door.   The seeds roll out onto the 3-lobed diving board.

 
4 Comments

Posted by on January 29, 2016 in Uncategorized

 

A Rolling Stone Actually Can Gather Moss

moss samantha humphreys

Photo by Samantha Humphreys

Mosses look ferocious under a microscope with hideous teeth. Good thing they are small, and never known to bite. The teeth, called the peristome teeth, regulate spore release, opening and closing in response to humidity changes. The entire moss life cycle is out in left field, but we can’t do it all today.   To take that turn on your own, BITE HERE

Peristome Cypress Creek Swamp

Peristome teeth

So what’s the big deal about that mossy magic carpet? For obvious starters, the rug insulates tree roots, retains moisture, cuts erosion, and sequesters nutrients.   No surprise tree roots sometimes congregate under mosses. Moss removal sometimes impacts the trees above.

Mosses are nutrient catchers.   Although they can obtain nutrients from soil, they have no roots or veins, and soil-absorption is merely one trick in their book. Mosses absorb nutrients also from direct exposure to rain water, mist, stemwash, dust, puddles, and poodles.   Rainwater arrives with dissolved nutrients, and percolating through the leafy tree canopy can enrich the drizzle. Direct nutrition allows mosses to colonize tree trunks, rocks, sand, and other places where others dare not grow.

In Florida mosses love palm and cypress trunks, presumably enjoying the nutrition washing down.   Palm trunks are a little spongy. Bald cypress, being deciduous, allows sunbeams down to the moss zone, and in a swamp. Mosses favor swamps.  The tips of cypress knees grow above their mossy green jackets.

cypress knees

Mosses hold water for long spells but eventually dry out into suspended animation. They are resurrection plants.   Upon re-moistening they pop awake in seconds—repeat—in seconds—experiencing an adrenaline rush plant physiologists call a respiratory burst.   In the wink of an eye a remoistened moss starts heavy breathing before photosynthesis takes charge.

moss dry 2 tablet 600

Respiratory burst, moss on a palm trunk on the PBSC campus.   Horizontal = seconds.   Vertical = carbon dioxide released (respiration).  Seconds 1-300 the moss was dry.   It was soaked with water at 300 seconds.  Immediately there is a big burst of carbon dioxide, peaking at around 625 seconds when photosynthesis seems to take over and start using more carbon dioxide than the plant is producing.

Nitrogen is the main nutrient and presumably most limiting.   How mosses obtain nitrogen is more subtle than mere manna from heaven. Nitrogen fixation (capture from the air) in nature can involve many species of microbes and associated plants, most famously legumes.   Mosses get their fix too. Certain species have symbiotic relationships with nitrogen-fixing photosynthetic (cyano)bacteria. Usually the bacteria live on the surface of the moss.   In some sphagnum mosses the bacteria inhabit the hollow leaf cells we’ll discuss momentarily.

moss iceland pat bowman

Moss in Iceland (by Pat Bowman)

Bear urine and decaying fish are reported sources of moss nitrogen.   How about dead bugs? In Iceland expansive rocky or icy areas lie under moss. Where does that nitrogen originate? Reportedly from nutrient-rich geothermal springs, these breeding gazillions of midges who swarm out over the mosslands and become fertilizer.

Icelandic mosses do something even weirder than eating bugs…they form “glacier mice,” rolling stones literally gathering moss.   A small stone on the surface of a glacier can grow a covering of  moss. It blows around, the mossy covering resisting freezing to the ice. The expanding mouse becomes a rolling planet inhabited by invertebrates: springtails, nematodes, and tardigrades. Probably the microinvertebrates among the moss leaves help churn nutrient turnover. Does the wandering mouse sweep up dead gnats as it rolls? That would be active hunting by a plant! Beats a sedentary Venus Flytrap any day!

Springtails, nematodes, and tardigrades…oh my…are typical moss-dwellers most anywhere mosses abide. The invertebrates dry out with the moss, and everybody slumbers until it rains again.   Tardigrades look under the microscope like  6-legged bears, and are called “water bears.” Mosses are their most famous habitats. Tardigrades may be the toughest animals on earth, having extreme tolerances in terms of salinity, drying, freezing, heat, and more.

Tardigrades alter their DNA when they go into their suspended dry phase, and upon resurrection they repair their DNA. It seems that millions of years of DNA repair has perhaps allowed genes from bacteria, fungi, and plants to enter the tardigrade chromosomes. Some of the tardigrade indestructability comes from the microbial genes they’ve adopted. There are more creatures. Mosses host nematodes, and mites that look like micro-crabs.

Springtails abound. Springtails are jumpy little insects primitive even by insect standards.   They pay their dues for a happy hoppy home by shuttling sperm from one moss to another.   The plants put out scents that influence the spermy little varmints, harnessing their hopping ever-so usefully.

springtail cropped2

This springtail came bounding out of a moss during preparation of today’s blog.

How does a moss make a monospecific lawn? To begin with competition is reduced in mossish extreme habitats. Many can creep and root, and they propagate from broken bits and pieces. Spores repopulate the carpet continually. Some have microscopic breakaway clonal units to go forth and multiply, and even lie dormant like seeds in the soil. Sometimes ants help with relocation. Mosses suffer little pest damage. Their anti-pest poisonous ways extend to inhibiting other plants. Sabotage is a good way to reduce competition.

moss carpet pat bowman

Moss carpet in VA.  (By Pat Bowman)   Probably under a foot of snow tonight (both of them).

Perhaps the most familiar moss to humans is sphagnum. It is the peat of bogs and peat moss.   It is where mummified pickled people turn up. It has served as bandages and diapers due to absorbency and antibiosis.   Peat is a staple in horticulture because it breaks down slowly and is extremely water-retentive. The ability to hold water comes from a network of big empty cells, each having a small opening.   The cells fill slowly and empty slowly, like holding a soda bottle underwater.

Sphagnum cells 600

Sphagnum.  Green cells mixed with empty hollow cells.

You may have gotten this far feeling that mosses are cute, or primitive, or maybe fun to grow. All true. Nice little plants. But don’t belittle a moss, for it may help us keep our cool.   Consider this, sphagnum is super-abundant in parts of the globe.   Peat bogs tie up enormous quantities of carbon dioxide. Biologist Chris Freeman at Bangor University is advocating a GMO sphagnum able to fight global warming.   What will they think of next?

Not a moss

 

 

 
7 Comments

Posted by on January 22, 2016 in Moss, Uncategorized

 

Canadian Horseweed Does the Twist

Conyza canadensis

Asteraceae

Today’s fieldtrip aborted…due to tornado warning? Ya gotta be kiddin me! A freakin’ twister. So my afternoon turned toward a different direction…looking into the recent listing of glyphosate (RoundUp) as a probable human carcinogen.   I’m not expressing opinions here other than, “well ain’t that interesting.”  This nice friendly blog is not for un-fun head-hurting controversy, so let’s merely ask how does RoundUp interface with a twister.

It is astonishing that weeds can evolve resistance to herbicides, survival of the fittest!   A lot have turned RoundUp-resistant, with one of the most resistant of the resistant being a native weed that’s everywhere and still overlooked…Canadian Horseweed. When I say everywhere, I mean everywhere: in every vacant lot, in every Florida county, in every U.S. state (yes, Alaska and Hawaii), in every Canadian province or nearly so, and almost surely on every continent except Antarctica. Yet who’d know it on sight? It looks like “weed,” although up close the flowerheads have beauty.

conyza far

All photos today by John Bradford

 

RoundUp resistance has turned up in this species across the U.S. and beyond. And that reveals some weird observations and questions.   First up, if resistance is so widespread geographically, did it evolve once and spread, or did it evolve multiple times in many places?  I don’t know but will vote for “lots of times.”   Convergent evolution at work.

The plot thickens.   Anybody attuned to GMO controversies dreads genetically introduced RoundUp resistance genes spreading from crops to weeds, making Superduperweeds.   But look what happened here…the weed did not receive resistance from a GMO crop, but rather cooked it up on its own.

And then it transferred resistance to another species, not crop to weed, but weed to weed by interpollination. Conyza canadensis shared resistance by hybridizing with Conyza ramosissima. The hybrids are more RoundUp resistant than the parent.

And there’s more.   How often do non-native invasives breed with native species?   Examples are few,  but there are hints in the literature of our native C. canadensis mixing genes with C. bonariensis, an invasive species called Asthmaweed here in Florida.

conyza side

So funny how one thing leads to another with strange twists. RoundUp resistance evolving in Canadian Horseweed reveals interspecific transfer of the resistance gene (but not as feared, from a GMO crop!). Attention to this brings up another fear come true: probable genetic pollution of a native by an invasive, although in weeds where nobody would notice or care.

conyza flower

And speaking of odd twists, here’s another.   Look up any smelly plant and find the usual uses against standard human discomforts. But here’s one you don’t often encounter, and it may be handy knowledge on a chilly night. Seems Horseweed puts the friction in primitive fire starters.

 
8 Comments

Posted by on January 15, 2016 in Canadian Horseweed, Uncategorized

 

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Pickerel Weed is Stylish

Pontederia cordata

Pontederiaceae

Relevant review of basic flower structure: POLLINATE HERE

Fieldtrip rained out yesterday, so in honor of the drizzle, here’s a wet weed in flower a little this week. Pickerel Weed is one of those South Florida beauties familiar also to frosty northerners, My earliest recollections of it come from maybe age 10 along Canadian lake shores and rivers.

pontedaria cordata far

Pickerel Weed (by John Bradford)

Funny how aquatic plants, Sagittaria, Wild Rice, Water-Chestnut, Cat Tails, and many more provide so much starchy food.   Pickerel Weed has served as sort of a “grain,” the seeds nibbled like nuts or ground for meal. But….reinforcing my usual spirit, please don’t eat nature…note that one of the few historical medicinal uses is as a pre-European oral contraceptive. “We’ve been living natural and all  out here off the grid but just can’t make a baby.”

 

Pontederia cordata fruits

Immature fruits (JB)

And some nature-eaters have suffered allergic mishaps and even intoxication, not to mention whatever water pollution sequesters in the plant.

pontederia cordata close

By JB

A bee by name of Dufourea novaeangliae likes Pickerel Weed, gathering pollen for its brood exclusively or nearly so from those purply-blue blossoms. The bee burrows into stream or lake shores near the PW. Not too surprisingly, the bee’s geographic range is similar to that of the plant, which, however, has a broader distribution, especially to the south.   Additional visitors include several more types of bees, butterflies, moths, and even hummingbirds.  The preferred customers are Bumblebees.

pontederia palmer cook

Bumblebee loves PW (by Palmer Cook)

Bumblebees engage in a type of foraging called traplining, where they visit the same traps (food sources) repeatedly. The stops around the trapline itinerary must provide awards over an extended period.  The PW flower spike makes hundreds of single-day flowers during its long life, with some opening anew each morning as old ones become fruits. A patch of pickerelweed offers flowers for the entire season, with that big yellow spot on blue background apparently advertising, “open for bees-ness!”

open

 

So far, ho hum, that’s all textbookish, but also a nice buildup to the good stuff, so here we go. The flowers have an unusual characteristic called tristyly (TRY-style-ee), that is, they come with styles in three different lengths on different individuals.   Helpful reminder: the style is the elongated part of the floral female unit, receiving pollen on its tip. Stamens make the pollen, likewise at their tips.   So then, different flowers on different individuals with styles of different lengths receive pollen at different depths in the flower: outside the entrance, at the entrance, and deep within.

This may seem like this “wherever you drop off the pollen” flexibility accommodates many different pollinators, from ones who flutter outside the door, to those who push right on in. No doubt true.    But there’s more to it.

Remember, it takes two to tango, and the stamens come in three lengths also.   Now pay attention: Each flower has stamens of the two lengths that do not match the style length of that flower. Huh?   Let’s say you have a short-style flower, then the stamens are of the middle and long lengths only, sans shorties.   Got it?   What are the stamen lengths in the mid-styled flowers? Answer, short and long.   Another way to look at it is that each flower has three positions, short, middle, and long. One position is occupied by the style; the stamens occupy the other two positions.

pontederia - Copy

Review:

Long style: stamens middle and short

Mid-length style: stamens long and short

Short style: stamens middle and long

But why?   To avoid self-pollination.   If a long-styled flower also had long stamens, those long stamens would deposit pollen onto the adjacent long styles in the same flower. Additionally the long stamens would dab pollen onto pollinators positioned to brush back off on long styles of other flowers on the same plant. Self-pollination is severe inbreeding, not good in humans, in Golden Retrievers, or in Pickerel Weeds.

And chew on this: a rhizome-connected colony of Pickerel Weed is one big sprawling individual genetically speaking, even if it looks like separate plants, so any pollen transfer within that extended colony is self-pollination.  With the no-stamens-at-the same-length-as-the-style policy, the pollinator must carry pollen to a different genetic individual for effective cross-pollination. A long-styled colony must receive pollen from mid-styled or short-styled colonies. Cross-breeding is enforced just like island-dwellers court spouses from different islands.

Confusing? Naw, with tristyly you don’t pollinate your own flowers even though all the while you’re catering to diverse pollinators. Pretty slick for a swamp weed.

short style 4.jpg

Short style flower.  Two stamens visible (one damaged)

 
10 Comments

Posted by on January 9, 2016 in Pickerel Weed, Uncategorized

 

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Muscadine Grape: big history and tiny hidy-holes

Vitis rotundifolia

Vitaceae

 

vitis rotundifolia fruits

Muscadine Grapes (by John Bradford)

John and George savored the kind of weather today, the first day of 2016, that migrates snowbirds.   A slice of heaven complete with trapdoor spiders, antlions, dragonflies, and delicate white mushrooms in a dry sand pine woods near Hobe Sound, Florida.

 

vitis with dragonfly

uscadine with Dragonfly (JB)

One of my running themes in botany is that a trip to the local state park reveals more fascination than an eco-tourism trip to Shangri-La with a khaki-clad guru pointing out some exotic orchid.   The very thing that makes nature so much fun is its universal accessibility. So today’s state park marvel is Muscadine Grape.   Everybody sees it, or trips over it, one of the most abundant lianas everywhere you go.   It has heart-shaped leaves with big marginal teeth.

Vitis rotundifolia

(By JB)

Muscadine has odd features, even compared with other grapes.   Most grapes have 38 chromosomes, but Muscadine and a few others have 40, making it tough to hybridize.  It does not graft well with other grapes, although you can graft Muscadines onto one another.

The flowers are usually male and female on separate plants.   And the stems are a little weird, because, although they climb by tendrils (little clingy fingers), they also can sprout roots.   The roots either remain small until the stem contacts the ground, or alternatively much later, the roots dangle like cables from the woody stems high in the tree canopy.   In most grapes the tendrils are forked,  contrasting with the unbranched tendrils in Muscadine.

Vitis rotundifolia flower

JB

A hand goes up in the back of the room:

“Do they use Muscadine for wine?”   You bet your sweet bippy. It is the oldest cultivated grape in North America, which is easy to assert because Native Americans had the pleasure before Europeans got the knack (see below). Today there are hundreds of cultivars, including the Scuppernong Grapes, originating in North Carolina.

A jumbo Scuppernong vine on Roanoke Island is one of the most intriguing individual plants in all the U.S.   The exact history is unknown, with different versions in different references, but here are the broad facts. The “Mothervine” appears in account(s) by original settlers on the Outer Banks in the 1500s, with Revolutionary War soldiers chiming in on it 200 years later.  Fast-forward two more centuries.  The beast remains alive, well tended, and big despite an accidental brush with road-clearing herbicide. The trunk cluster is multiple feet in diameter, and the leafy bits supported by trellises covered 2 acres before some trimming.

The Mothervine probably is the horticultural work of Native Americans. Were Native Americans in eastern North America wine snobs? Reportedly so, to a limited degree. Did they fancy sun-dried grapes? Actually yes, according to a British sea captain in 1565. It’s only raisin-able after all.

Vitis rotundifolia babies

Simple tendril (JB)

Muscadine and other grapes have a secret. Flip over the leaf and look closely where the petiole joins the blade to spot tiny caves with the doors surrounded by shaggy teeth.   These “domatia” are homes to mites lurking like the Once-ler in their tiny lerkims.

Vitis domatia4

The domatia look like caves (microscope picture)

So, why you ask, would a plant bother to host mites? They’re good predatory mites, it seems, interpretably guarding the plant from bad leaf-munching mites as well as from fungi.

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vitis domatia AI

Have a Mitey Fine New Year

 
12 Comments

Posted by on January 1, 2016 in Muscadine Grape, Uncategorized

 

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Water-Lettuce – You Can’t Get It Wet

Pistia stratiotes

Araceae

evan 788

Honeymoon salad (lettuce alone) (by Evan Rogers)

John is away for Christmas, so my substitute field companion today was son Evan, down from North Carolina with camera in hand. We’ve been out in recent days hanging around with hawks and sandhill cranes, mostly by canoe with water-lettuce impeding navigation.

hawk

Hawk guarding the marsh (by Evan Rogers)

Is water-lettuce native? One of my most-used local plant handbooks says, “native to Africa,” but that’s the trouble with single sources. Weeds get around, and the small seeds are conceivably transported by migratory birds or even on floating debris.

evan 852

All strung together by stolons…canoe traps (by Evan Rogers)

Who’s to say it didn’t arrive on is own? Aroid specialist Sue Thompson in the Flora of North America is open-minded (and see Notes below):

“Some botanists consider the genus to have been introduced into the United States and many regional floras state that fruits and seeds are not produced in the flora area. However, s Seeds with high rates of germination have been reported from many sites in Florida, however … The status of Pistia as native to the United States has not been resolved; available evidence suggests that it is indigenous.”

Whenever and however it arrived, Water-Lettuce goes back in Florida about as far as botanical exploration.

Water-Lettuce is one of the odder members of the odd Aroid Family, known to native plant enthusiasts for arrow-arum, golden-clubs, and jack-in-the-pulpit. Gardeners and florists love aroids as anthuriums, philodendrons, and spathiphyllums. Funeral homes like them too, as calla-lilies. The sign of an aroid is having small flowers in a spike called a spadix, and a colorful specialized leaf called a spathe wrapped around the spadix.

IMG_8344

Pixie spathe  (white)  around spadix

The spathe and spadix in water-lettuce are pretty, reminiscent of a tiny peace-lily. The folded water-lettuce spathe has two expanded openings, the top gap allowing a whorl of male flowers to jut out; below those a single female flowers peeps from its own gap.

IMG_8389

The yellow star is a whorl of male flowers. Below it is one white female flower.

Naturally hydroponic, the fuzzy rosette floats with its roots dangling.   With full sun, swimming in water, nutrients in the soup, and stolons to sprawl forth and conquer, this weed can expand!   That’s bad if it clogs and shades waterways, jams pumps, or decays and stinks.

evan 818

Dangling participles (by Evan Rogers)

On the good side, however, here’s a plant able to pull “sewage” nutrients out of over-enriched waters, suck heavy metals and pesticide residues out of canals, and generate truckloads of biomass if you want biomass. It is not a true lettuce so put away the croutons, but water-lettuce is easily generated compost, although not on edible crops.  And we all cheer for biomass biofuels not competing with food crops, fertilizer-free, and providing bioremediation as a bonus.

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Notes:

Just try to get it wet:   SPRINKLE HERE

For more on the native vs. non-native question CLICK

Crane2

Seed spreader (by Evan Rogers)

 

 

 

 
12 Comments

Posted by on December 25, 2015 in Uncategorized, Water-Lettuce

 

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