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False-Pennyroyal

Piloblephis rigida

(Piloblephis = eye-lash hair.  Ridida means rigid, describing perhaps the leaves? )

Lamiaceae (Mint Family)

Rain prevented today’s usual Friday fieldtrip.  Unable to abide a botany-deprived day, optimistically  between rainshowers I scooted to a nearby patch of False-Pennyroyal to savor a fuzzy  stinky mint of open sandy places, such as the pine flatwoods savanna near my home.  Got there and it poured.

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It forms big patches. Photo by John Bradford.

Mints smell like mints, right?  When this species is putting out, walking through its habitat you sniff it before you spot  it.    There’s an aroma of things that end in -ol, such as pine-sol, menth-ol, and eucalypt-ol.    (For sticklers, I’d say it smells like monoterpenoids, common aromatic oils in mints and many additional aromatic plants.)    The nice essences are probably protection from herbivory, although additional functions are conceivable,  perhaps  light-protection or suppressing surrounding vegetation.   And the security is not absolute, as today’s furry friend hosts at least one species of mealybug.  There are some old uses for the False-Pennyroyal fragrance such as guarding pooches from fleas and as tea and flavoring.  I just like to pick it for a whiff.

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Polka dotted blossoms, by JB

How many plant genera are limited to Florida?    Piloblephis almost is.  Interestingly, it turned up also in the Bahamas in the 80s.  Native there or not, who knows?   People have shuttled between Florida and the Bahamas for a heckofa long time, and the plant is easy and pleasing to cultivate (and allegedly improves disgusting turtle stew).  Birds could carry it to offshore islands.  Not to mention hurricanes.   Even maybe floating. The “seeds” are well designed to get around.

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Flowers in “cones” by JB

Like a normal mint, the fruit divides into four “nutlets.”  These separate into what look like four tiny  blackish “seeds” small enough to stick in the mud on a bird, on a shoe, on a floating log, or on a pineapple crate.  The nutlets come packaged in a fuzzy “bag” made from the flower sepals.  The bag could fly on the wind, resembling the parachute-fruits from many members of the Aster Family.

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These feathery bags each hold four itsy bitsy seedlike nutlets.

The polka-dot flowers peek out of leafy spikes resembling soft conifer cones.  The bracts covering the cones can turn bright pink mixed with green at fruiting time.  Is the raspberry sherbet pigment a sunscreen guarding the embryos within?

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Pink cones, the mature nutlets inside.

Or…and this is an irresponsible baseless speculation …wouldn’t it be fun if that eye-grabbing pink helps draw birds or other wildlife to peck, nibble, and disperse the nutlets?

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Wasp believed to be  Agapostemon splendens (do not trust me, my wasp expertise is Google) .

 

The drought-resistant leaves look like conifer needles covered with the hairs responsible for the plant’s eyelash name.   The furry fuzz gives the plants a grayish sheen, probably reflecting away excess Florida  sun.  The hairs come in varied lengths.   Most end in a point, and some  end in a globe, looking like a tootsie roll pop.   The pops  seem to be the (or a) source of the oily essence.

The multi-length pointy hairs probably enforce a “don’t eat me” policy, and also might cut down on sun and wind.

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Ammophila procera, if my wasp-Googling is correct. Same species as last week on Hyptis.

There’s no single OMG! thing about False-Pennyroyal, yet it is overall an intriguing and assertive eccentric,  spreading into round patches several feet in diameter,  having  flowers in cone  wasp perches, bearing needle-shaped leaves having silver-gray coloration, emitting an aroma like kitchen bug spray, producing fruitlets in fringed bags behind bright pink bracts,  and  skipping to the Bahamas.

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Some of the coolest species are right under our noses,  and our nose knows.

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Eyelashes.  Pointy, long and short, and oh look, a tootsie roll pop full of stink oil.

 
4 Comments

Posted by on December 9, 2016 in False-Pennyroyal, Uncategorized

 

Clustered Bushmint  Pops the Pollinators

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Wasp visiting Hyptis alata, courtesy of John Lampkin

Hyptis alata

(Hyptis comes from Greek for “turned back,” maybe in reference to the way the lower petal lobe repositions after pollination.  Alata means “winged,” apparently describing the broadened leaf stalk.)

Lamiaceae (Mint Family)

 

Today was as heavenly  as weather gets, deep blue sky, breeze, perfect temperature for penetrating the Kiplinger Nature Preserve swamp.

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Swamp creature

Not on a boardwalk, nor on a trail, I mean climbing over dead trees tangled in vines.  We explored  deeper into the vast Kiplinger jungles than any mortal human, into the belly of the beast.     Not unrewarded though, along the way seeing Dahoon Hollies more laden with red berries than with green leaves, Royal Ferns a dozen feet tall,  trees festive with hundreds of big pink climbing Carolina Asters,  a pair of Hooded Mergansers on the marshy pond,  15-foot gators drooling for human flesh, vipers in every shadow, and today’s mint, deep in the shade, although vastly happier in a sunny marsh.

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Hyptis alata by John Bradford

Hyptis alata populates two different homelands with a massive gap between, one subpopulation in the southern U.S. and associated Caribbean,  and another subpopulation in S. Brazil, Paraguay, and Argentina.  The two existed as separate species until joyous unification in 1983.

The flowers are odd in this and related species.  The crowded blossoms are in tight clustered head.  A visiting pollinator can service multiple flowers in the same head, although only a fraction of the blossoms are open at once, compelling pollinators to move from plant to plant.    The recorded visitors include bees, butterflies, wasps (see shots by John Lampkin), and hummingbirds.  And I’ll bet certain types of flies come along too.

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By JB

The pollination mechanism is explosive and weird.   The flower is tube-shaped with five lobes at the rim of the tube. Four of the lobes are “normal,” the fifth lobe lies at the doormat entrance to the tube on the path to nectar within.    This odd shoe-shaped lobe houses the four stamens (pollen-producing organs).

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The 5th lobe yellowish and hairy, jutting to the right, not yet popped.

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Fifth lobed unpopped closeup

As the stamens grow they build up tension pushing against the lobe surrounding them, like toes in a tight shoe.    When a landing pollinator touches the loaded lobe, the stamens pop up and impact the visitor from below, depositing pollen on its underside.    Surprise!  The now-empty lobe soon dangles down dejected.  The stamens likewise, their pop-up job done, bend aside to let the style (pollen-receiving organ) take over, converting the flower from functionally male to functionally female.

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The empty shoe hanging down, the freed stamens and style above it.

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The hairy empty shoe lobe below the stamens, closeup

Normally biochemistry is too boring for a hopefully fun wildflower blog, but in Hyptis the biochemical story is so related to real-people experience  let’s go there.   We’re talking about modern chemotherapy drugs.

As prelude,  a quick lesson from my “Concepts of Biology” class.   The DNA double helix, our genetic material ya-know, is such a complex twisted stringy molecule it doesn’t take much imagination to wonder how it functions without tangling.   Answer: DNA does tangle in ways that would be fatal if not for enzymes that unsnarl the snarls.   Enzymes known as topoisomerases snip, untangle, and then repair the tangled DNA.    If you have a snarled chain you could fix it if you cut links out, then separate and straighten the segments, and then reattach the fixed segments by forging new links.    The ability to untangle and fix DNA is especially critical at the time of cell division.

Prevent the untangling and you have a lethal poisons called topoisomerase inhibitors, with pharmaceutical examples being etopside (Toposar), teniposide (Vumon), and etopofos (Etophos).   They suppress cancer because a growing tumor needs rapid cell divisions more than the rest of our body does, where of course we do experience limited toxic side-effects.

All three of the drugs listed above are based on the natural botanical toxin podophyllotoxin, originally from the genus Podophyllum (May Apples).    In addition to cancer drugs, podophyllotoxin under various brand names kills warts more effectively than spunkwater.   This cytotoxin is scattered in the plant world, with only a few producer species  known so far, including a species of Hyptis.   If discovered in one Hyptis, then probably awaiting discovery in others, including plausibly our own poorly studied Clustered Bushmint.

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By John Lampkin.   The traps are sprung.

 
5 Comments

Posted by on December 2, 2016 in Clustered Bushmint, Uncategorized

 

Willy and the Dangerous Doodlebug

An Existential Kiplinger Tale

If you wanted to pinpoint something in nature to undermine the theory of evolution, I’d suggest the Doodlebug,  one improbable piece of creation.      As a biologist firmly marinated in evolution, I still scratch my head over how an insect larva could evolve the practice of digging a death pit, sitting in the bottom waiting for ants to tumble in, and then flinging sand on the victims to knock them down into the fatal funnel   I mean come on now, flinging sand!?   I’d like to see the incremental series of evolutionary steps leading to that!  (Do not get me wrong, it happened, and the fact is, today’s insects belong to the large Lacewing Family, with a fierce menagerie of predatory larvae.)

Doodlebugs owe their old-fashioned name to their squiggly wiggle lines in the sand.   They are be better known these days as ant lions, such an apt name.

We did not want to dig one up to its peril, so it was more lion-friendly to provide a link so you can view the hideous microbeast extracted from its conical pit.  CLICK  (And no, we did not plop an ant into a lion’s den.  All events today were purely observational.)   Those jabberwock jaws chomp with injection needles on the inner surfaces to shoot poison into the prey, and to suck out its vital juices.

Everyone in a warm dry place has seen the little cones of uncertainty, depending on the species, say an inch deep and 2 inches in diameter in dry sand, often but not necessarily under an overhang.   Surprisingly, the species are quite varied, over 20 in Florida and vastly more globally.

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Adult on John’s screen, by John Bradford

After lurking in a hellhole for months the larvae form spherical cocoons to soon emerge as gorgeous lace-winged adults whose job is to mate and lay eggs in a brief multi-week sexcapades.   They hook up on trees, with pheromones implicated as their match.com.  The adults are nocturnal and go to light,  perhaps drawn collectively to translucent leaves in the gloaming or to moonbeam love beacons?   The light-attraction is key to human-ant lion encounters, as they flutter onto  screens blocking access to the wonderful lights just beyond.

What a pity we don’t sit on screen porches any longer.    We miss a lot of good bugs and all the  nocturnal froggie and katydid audio, not to mention evening porch conversation with trains in the distance. This summer camping in Michigan, the lightning bugs were magical deja vu glimmers of summers before Comcast.

You can now watch the lion-ant battle to the finish John and I witnessed today in Kiplinger.  DOODLE HERE for the action.

 

 

 
5 Comments

Posted by on November 18, 2016 in Ant Lion, Uncategorized

 

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Balsam-Pear, Balsam-Apple, Cerasee

Momordica charantia

(“Momordica” comes from Latin for bitten because the seeds look chewed.   Charantia is  perhaps an old name for this anciently cultivated species?)

Cucurbitaceae, the Gourd Family

Friday.   Cool. Sunny. Breezy.  Time to relax and enjoy the Kiplinger Natural Area.  Or cyber-enjoy it thanks to John’s evolving photo-study.   CLICK

A weedy alien vine in Kiplinger has quite a history.   Part of the reason it surfaced as interesting today is a patch by the entrance to a subterranean Gopher Tortoise burrow.   Gopher’s like tasty fruits, such as, well, Gopher-Apple, so today’s “apple” looks like gopher fare to me.  Now I have no evidence that Bilbo Baggins Tortoise put the seeds by his front door of his dugout bungalow.   But the alternative explanation, chance, is no fun, and being an election year, you can choose the truth you like.    I chose the tortoise deposited the seeds in the dooryard.

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Momordica vine to the left.  Tortoise hobbit hole to the right.

Living in the Caribbean, I came to know it as Cerasee as a valued medicinal tea.   The plant generates nearly every category of plant chemical WMDs, from alkaloids to steroids.   That ties in with ancient and sundry medicinal uses from its original Africa spreading to to India, Tropical Asia and beyond.  Med-apps are far too many to list, although they feature treating diabetes, plus such contradictory extra benefits as aphrodisia and induction of vomiting, hopefully not on the same evening.

Drug-loaded species attract research  attention, in this case in multiple connections including for antibiotics, anti-cancer compounds, and steroidal precursors.  Bitter principles in the fruit confer pest resistance, raising the eyebrows of agriculturists wondering if such defense may be bred or engineered into more vulnerable crops.

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The flowers.  Todays plant pictures by John Bradford.

So obviously,  do not harvest and consume it.   Rule of this blog:  never eat wild plants.

Cerasee has been a food in the Old World for hundreds or thousands (?) of years.   That may seem odd, given the toxins,  but then again,  as with many anciently cultivated species, folks long ago developed domesticated strains.  The Bitter Melon Karala from India  is an example, and there are several edible Asian cultivars.  The cultivated fruits vary in shape, flavor, and colors from near white or greenish to orange or red.  They range from a  couple inches long as in Florida, to about 18 inches in one or more cultivar(s).   According to research dating to 2004, evidence indicates a single domestication event followed by diversification and dispersal.   All of the cultivated strains differ genetically together from the wild(ish) species.

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Remember, the Balsam-Pear encountered growing wild in Florida is not one of the garden types.   How did it get here?  Probably from Africa during the slave trade.  Once on this side of the sea, the red-coated seeds allowed secondary dispersal by animals.  And by people too.

The bitterness of the fruit rind protects the seeds until they are ripe.  Then the noxious fruit opens to reveal the seeds rendered tasty and attractive by a red coating called an aril.

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The orange pod with its bitter rind.

The flowers are unisexual, both sexes on the same vine.  Apparently because the male flowers on the vine can pollinate the females on the same vine, the male flowers mature about two weeks before the females to encourage crossing with other vines before the opportunity for the extreme inbreeding of self-pollination.

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The fruit opens to reveal bird-dispersed (and tortoise-dispersed?) seeds with a fleshy red coating (the aril).

So then, back to the tortoise.  They have, I think, a lifespan similar to a human so they need Medicare pharmacy benefits too.   Maybe the tortoise in Kiplinger needed a little tonic tea, or maybe even a little turtle aphrodisia, bringing a few seeds to his sandy Hobbit-tat.

 
8 Comments

Posted by on November 11, 2016 in Balsam-Pear, Uncategorized

 

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Linden Leaf Hibiscus, Two Species in One Shrub

Hibiscus furcellatus

(Hibiscus is an ancient plant name.  Furcellatus means forked, in reference to the forked “antlers” at the flower base.)

Malvaceae

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All photos are H. furcellatus, by John Bradford.

One of the showier flowering shrubs around Southeast and South-Central Florida is the Linden Leaf Hibiscus, growing fast, and standing tall with big shocking very-pink blossoms all showy and decorative. The species is almost as ornamental as any garden-variety Hibiscus, and in Hawaii Hibiscus furcellatus is a garden flower, as well as one of the cluster of Hawaiian native Hibiscus species.   It once was widespread in Hawaiian lowlands just as it decorates wet soil Florida.

Linden Leaf Hibiscus has ancient history in Hawaii as a laxative, a nice example of an island culture finding the same use for a species distant mainlanders did, that is, Hibiscus species are sources of laxatives in other cultures.

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Note the barricaded flower base.  No sneaking in from the south flank!

Native to Florida, and native to Hawaii?  Isn’t that odd?   Yes, but then again the native Hawaiian flora didn’t flow forth from volcanoes.   Hawaiian botanists suspect Hibiscus furcellatus to have arrived by seed drifting on the ocean, probably from Central America.   How far from, oh say, Panama to Hawaii?  Wonder how long that floating pioneer seed was in the brine.

If a seed floated up onto a Hawaiian beach, it would have grown into one lonely plant.    Being solo, there would have been no mate to pollinate it, nor were its natural pollinators handy, but no worries.   Hibiscus species tend toward a self-pollination mechanism as back-up system.  They make vast seed crops in Florida, littering disturbed mud with countless seedlings.    The flowers “look” like they are fundamentally hummingbird adapted, but hummingbirds are sparse locally, so those profuse seedlings must come from bee-visitation, and/or from that self-pollination capability.

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Ant(lers).  Do the barricades protect the bud, or the ant, or the ant food?

 

,The flower owes its name “furcellatus” to forked antlers (modified bracts) surrounding the nectar-rich flower base in this and related species.    The antlers look like they block nectar thieves from side-stepping the front and center proper entrance.   And if the branched barricade is not discouraging enough to flank attacks, the outside base of the flower feeds guardian ants from “extrafloral” nectaries.

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Ant headed to nectary on flower bud

The early origins of Hibiscus furcellatus are a mystery to ponder.  Our species seems to be an ancient hybrid of two other species, having two different sets of chromosomes, one full set from each of its parents.  That would be like me having a full set of human chromosomes AND a full set of chimpanzee chromosomes.  One Hibiscus furcellatus chromosome set (called G) probably originated in Africa, as tough as that may be to imagine.  There remain on Earth other species having the G chromosome set uncombined with others.   The second chromosome set (called P) probably originated in the New World where there exist a total of four species having the same ancient GP combo, despite the absence of any known extant species with P alone.   Maybe some bored future genetic engineer will separate the two chromosome sets and re-constitute the two ancestral species.

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Seed capsules

 
3 Comments

Posted by on November 4, 2016 in Linden Leaf Hibiscus, Uncategorized

 

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Saltbush

Baccharis halimifolia and local relatives

(Baccharis comes somehow from Bacchus, the god of wine.  Halimifolia refers to a different plant with similar leaves.)

Asteraceaeae

 

Working in the Kiplinger Natural Area  in Stuart, Florida, today, John and George enjoyed a dozen wildflowers in peak display, so beautiful:   White-Snakeroot,  Bluecurls, Liatris, Coin-Vine, and so many more.     In the garden of native delights is a fall-flowering species with curious attributes,   Saltbush, Baccharis halimifolia.    In our area we have also Baccharis glomeruliflora (flowers in tight clusters) and B. angustifolia (narrow untoothed leaves), representing a widespread genus of over 350 species.

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Hammock Snakeroot by John Bradford

For starters,  the distribution of Baccharis halimifolia is odd, with a population in eastern Canada, then a gap of over 400 km to New England, down the U.S., into the Caribbean and Mexico.    This is one widespread plant.   And then some:  it has escaped cultivation or otherwise invaded around the globe, even in the Mediterranean and in Australia, where it is a pest battled with a destructive rust fungus.   The species is not welcome in many places because it accumulates in pastures and is fatally cardiotoxic to some grazers.  I don’t know where the poisons reside, but the leaves have secretory glands probably responsible for protective secretions.

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Saltbush in bloom  by JB

The individuals are separate males and females (proper term,  dioecious, die-EE-shus).  That’s no biggie,  but the odd thing is, how many dioecious plants have male-female differences other than the flowers?   That is rare in my experience.  According to a USDA publication, the males have longer shoots, softer leaves, faster growth, and earlier seasonal senescence than the females.   Sounds like maybe the males are more “designed” to reach out and scatter pollen, in contrast with females who need more sturdiness and an extended season to make fruits.  Pollination is by wind and by insects.  The small wind-dispersed fruits are on parachutes.

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Female flower clusters by JB

Species of Baccharis have an adaptation sometimes associated with salt-tolerance…water-emitting valves called hydathodes at vein tips.   Hydathodes resemble the drip-emitters used in irrigation, flushing out water and anything in it such as excess salt.

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Baccharis hydathode by Dr.  Bob Wise, Univ. of WI Oshkosh, with permission. Scanning electron microscope view.

John and I have been watching ants scramble around the Saltbush.  The ants come marching two by two to tend sucking insects.    The sucking insects we’ve seen are aphids and perhaps two species of scale insects.  (Baccharis is the main Florida host for Green Scale.)  Such insects “suck” sugary sap from the host plant.   The sugary goo passes through the lil’ sucker to drip forth from the other end as “honey dew.”   The honeydew can spread and grow black fungi called sooty mold, and some of it follows a more interesting path as ant food.

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Ant on Saltbush today.  With scale insects and sooty mold.

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Green Scale on the leaf today

That ants crave honeydew and tend its makers like farmers tending cows is well studied, producing conversations about three-way symbiosis: win-win-win.  The plant gains armed guards.   The ants get sweet treats.  And the sucking insects, well, if they are not merely exploited, might get help in dispersal and might be under the protection of their creepy little shepherds.

CLICK to see a similar symbiosis, of all things, on the inside the stem of a different plant.

 
4 Comments

Posted by on October 28, 2016 in Saltbush, Uncategorized

 

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Zombie Plants – The Green Undead Awaken on Halloween (if it rains)

 

(More technically, Poikilohydric Species play possum)

This week’s fieldtrip is tomorrow, so with no crystal ball, so I’m taking a little pre- trip literally to the back yard.   Today we’re talkin’ plants with no roots and no internal plumbing, or almost none.    All water goes in through the foliage as it rains, but when dry the plants look and act like death, until resurrection when soggy returns.     Although there is a spectrum of possibilities and variation in mechanisms,  the interesting cases are not mere wilting or  closing up shop, but rather extreme deeply suspended animation, essentially lifeless.   You wonder how long a plant in that state can rise from the grave.  Answer: long.

Remember the term poikilohydric (= plant zombie).

Florida is a great place to encounter these resurrecting oddballs.   We have a lot of epiphytes, some of which behave poikilohydrically, most famously our Resurrection Fern (Pleopeltis polypodioides) as photographed by John Bradford:

Spanish-Moss and its cousin Ball-Moss (Tillandsia recurvata) may not be full-blown dry-and-diers, but they get mighty thirsty hung out to dry.

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Ball-Moss on tree trunk

These species use umbrella-shaped scales (think micro-toadstools for second analogy in one sentence) to capture and distribute rainfall.

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The scales on Spanish-Moss leaf.  By Robert Wise, Ph.D., Univ. WI Oshkosh, with permission. Scanning electron microscope. The scale is anchored like a toadstool at the middle.

One drop can irrigate an entire scaly leaf as we will see momentarily.  The scales have intricate structure, and flip down in the presence of water.  Water moves from scale to scale like an electric current traversing a wire.  Watch this video of one drop going a long way. CLICK TO SEE!

What is so astonishing is the depths of the Snow White slumber.  Hard-core cases go through profound internal biochemical and structural reduction and disassembly.  Internal membranes collapse or disappear.   Special protective proteins, enzymes, and electrolytes form.  Internal cellular components vanish.  Some go so far as to dismantle their photosynthetic apparatus, and reconstruct it upon remoistening.    Seen with a microscope the leaf cells look deceased.  Then it all comes back.

Below is a series of photos of a liverwort from a tree in my yard.  After the photo showing the liverwort on the hot dry bark are three microscope views of the same leaf at the same magnification, the first snapshot while dry, the 2nd  photo 15 minutes after re-moistening, and the third shot about an hour later.   Notice that in the dry condition the cells look hollow with no apparent chloroplasts (the green disks in the later photos).  The chloroplasts are either gone  or collapsed into a thin film against the outer walls of the cell.   Yet just minutes post-moistening chloroplasts appear magically, and after an hour the previously deadish cells look perky.

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Liverwort on hot dry tree trunk

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A dry leaf, microscope view, from the liverwort.  Notice the hollow “empty” cells.

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Fifteen minutes after wetting.  Chloroplasts (little green dots) already returning!

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About an hour later

The reappearance of chloroplasts is a jiffy.  What is truly mind-boggling after wetting, however, is the instant return of respiration, intake of oxygen and expulsion of carbon dioxide, such as our breathing.    In their dry state poikilohydric plants show no detectable, biological activity.    Within seconds of rewetting carbon dioxide exhales.  (The very first carbon dioxide given off is probably not from metabolism, but merely forced out of nooks and crannies by the wetting, then metabolic carbon dioxide from life renewed follows in a few more seconds.) The graph below shows warp-speed carbon dioxide release by a remoistened moss.   So fast it’ll make your head spin.

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Rapid carbon dioxide release.   Moistening was at about 650 seconds.  The fast dip happened as the water was squirted onto the dry leaf, perhaps from the gases in the pipette.  The mall first peak near 700 seconds is probably non-metabolic carbon dioxide, followed by the broader breath of metaboliic carbon dioxide as Rip Van Winkle awakens.  No time wasted!

Why that burst happens is not well understood.  I mean, why would the plant start respiring, burning sugars, before it is ready to replensih its own sugars by photosynthesis.  One line of thought is metabolism revs up like “gentlemen start your engines” before the transmission engages, that is, before all the plant’s membranes and internal structures return to working capacity.    The slumbering plant needs to work fast to exploit a fleeting cloudburst.

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Poikilohydric lichens by John Bradford, followed below by moist and dry Selaginella by JB.

The distribution of plants with poikilohydric superpowers is broad and spotty.  The “lower” plants with no roots or veins need it, having no ability to take lift water from the soil and no pipes to move it internally:  some algae, lichens, mosses, and liverworts.     Rootless rain dependence may seem like a drag,   but it is a plus for living rootless on tombstones, telephone wires, and tree trunks.  Some plants with roots and veins, “vascular plants,” have poikilohydric representatives, including fern allies (our local Selaginella),   ferns, and assorted Dicots and Monocots, including a few grasses and sedges.

You might ask, how could so many different unrelated  plants come up with the same bag of tricks?  Well, convergent evolution is not rare, but more tantalizing, the ability of mature plants to go into quasi-death-dormancy is mirrored in something all seed plants have—seeds.  The genetic mechanisms that allow seeds to lie dormant and dry for centuries might extend sometimes in some species into adult life (and death, and life).

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Hanging around the liverwort tree, by Donna Rogers

 
9 Comments

Posted by on October 21, 2016 in Uncategorized

 
 
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