Pink Redstem

Ammannia latifolia

(Johannes Ammann was an 18^th Century botanist.  Latiflolia means wide leaves.)

Lythraceae

John and I worked at Haney Creek Natural Area near Jensen Beach, Florida, this week.  Much to my delight as a lover of things in wet places, we saw an old wetland oddball plantfrind, always under-appreciated.   The sort of plant you step on looking for something “interesting.”    It is all interesting if you look closely, or if you read research by other people, especially other people with an electron microscope.   Today I’m paraphrasing an eye-opening paper by Dr. Shirley Graham (in the Journal of the Arnold Arboretum, vol. 66).  Because the work dates to 1985, I’m confident Dr. Graham and the Journal would have no objection to reappearance in a 2019 blog, and I sent her an e-mail to make certain.

Today I was doing what I like to do, walking along the dried out shore of a nearby stream-canal where only two living things were visible on the barren mud, one a green alga, the other, as at Haney Creek previously, scattered individuals of Ammannia latifolia livin’ the vida sola.  Just desolate mud, a little algae, and big red Ammannias.

What dis the Ammannia and I have in common?  We were alone on the  lifeless mud.

Life “on mars” takes a fairly special plant.  Ammannia has some obvious advantages for places that alternate between flooding and drought, with suffocating soil.    It is a wee bit succulent, has rugged leaves, has red coloration which may be sunscreen,  and has padded little pea-sized capsular toothcup fruits.   The flowers may or may not have petals, that’s odd, and it can sometimes, or perhaps predominantly, set seeds without benefit of outside pollination, a handy trait in a lonely pioneer.  The pollen-making anthers can break off and adhere to the pollen-receptive stigmas in the same flower assuring self-pollination emphatically.  The roots tolerate saturated mud.

That is all well and good, although perhaps unthrilling.  The magic is in the seeds, as Dr. Graham related.  The electron microscope photos below are from her 1985 publication.

The seeds are  packed a couple hundred per fruit.   They float, and have a special mechanism to do it well:  On one side of the seed there appears a small puffed up beer belly, a flotation device, which collapses when the seed dries.

Seeds photographed today.  The one on top is dry.  The one on the bottom is moist,  the puffed out float on the left. with light shining through.   As the seeds take on water out pops a bubble as seen lower right.

Ammannia seed showing the pufferbelly.  Photo from sources noted in text.

Even weirder, there are hairs on the inside of the seed coat, wrongside-in.  When the coat is moistened the hairs pop outward to become spikes like the antennae on Sputnik, where they may help water enter the seed.

Seed hairs moistened and sticking out.  Photo source mentioned in text.

The moistened seeds become a little sticky, which may help them grab hold to a final sprouting site, or may help them cling to a bird’s leg en route to the next aquatic environment.    The seeds are willing to germinate in a few days under favorable circumstances,  and if things aren’t optimal some are patient and tough, reportedly germinating from dried museum specimens 27 years old.

 

A Sabal Palm Tree is a Universe — From a Sap Beetle Standpoint

Sabal palmetto

Arecaceae, the Palm Family

Sap Beetle  Brachypeplus glaber

In the horticultural world vertical gardens became faddish a few years ago.   Nothing new there:   Cabbage Palms invented the concept, some of their trunks being vertical jungles, although other individuals can be bare and clean.   Many Cabbage Palms retain  broken-off leaf bases which turn into hundreds of little natural flower pots filled with spongy detritus.  Somewhere I read a list of around 60 plant species occupying Cabbage Palms, merely in one locality.  Some of the hangers-on are rooted on the ground and climb; others root on the palm itself, especially in those fertile leaf bases.

It is fun to walk and gawk at Cabbage Palms to see who is hanging around, and far more fun to wonder about the interactions among the species.   What nutrients, or toxins,  or hormones from the plants perched up high  wash down the trunk and suppress, or favor, species lower on the totem pole.  Some species may use allelopathy (natural herbicides) drizzling down the trunk to discourage competitors taking hold below.  The nutrient cycling patterns would probably amaze, if only we knew.

Corkystem Passionvine enjoying the palm trunk.

The species distributions up and down the trunks do not seem random, although unraveling suspected patterns may be complex or subtle.  Cabbage Palm ecology runs deeper than meets the eye.  The tree has a lot of hidey-holes, and its microscopic life is no doubt a realm of secrets.   The micro-hideaways are where we are headed now, thanks to a team of entomologists.

Honkin’ big hanger-on…Strangler Fig on the Cabbage Palm.

In 2014 Andrew Cline and collaborators explored a remarkable multi-species ecological web on Cabbage Palms.   Virtually everything I’m about to relate comes from their research, linked below.

Join me now at the senescent flower stalk bases still held on the tree.  Any suburban homeowner dragging the fallen inflorescences from their St. Augustine lawn can see layering around the stalk bases.  During yard cleanup however, we may miss all the fun in the layers, the lair of a sap beetle, Brachypeplus glaber, found in this niche essentially exclusively.  Oh-no, a “sap” beetle!   Does it suck sap and disrespect  our state tree?  No, apparently not, its diet is more complex, and the beetle perhaps even benefits its palm host whose flower stalks are the insect’s entire life-bringing universe.

CLICK to see the beetle

Enter a third species into the plot:   The palmetto scale insect Comstockiella sabalis sheds its skins.   Our sap beetle eats the skins in a handy act of recycling.   Great , now move on:

Now come the fungi.   The beetle has a tight relationship with a yeast, Meyerozyma caribbica.   The beetle, including its larval stages,  lives among the yeasts, eats them, and apparently hosts them as internal symbionts.   The same yeast is a known digestive helper in other insects. The entomologists suspected the yeast to be so potently antifungal  as to be of potential medical interest.

Yeasts are not the only important fungi in the story. The main diet of our sap beetle is filamentous fungi, particularly from the genus Fusarium.  Somehow the yeasts seem to help the beetle deal with the Fusarium.  Maybe they constrain it to a dietary level rather than allowing the pathogenic fungus to overwhelm the inflorescence too rapidly, destroying house and home, although that is 100% my speculation.

Fusarium fungi are plant pathogens, and anything that eats the Fusarium or suppresses Fusarium  might be defenders of the palm.

The tale of the sap beetle et al. can lead to just one “sappy” conclusion.  You guessed it.  Here we have a case where an insect and its yeast associates could protect the tree at its vulnerable growing crown right where infective fungi are most unwelcome.   Would residential applications of insecticides and fungicides disturb an intricate and possibly valuable beete-scale insect-yeast-palm-Fusarium microcosm?    And, by the way, where does that little ecoweb go when you “hurricane prune” a Cabbage Palm’s crown down to just a few leaves?

 ———————————————————————————————-

A few species hanging around on Cabbage Palms

Algae and Cyanobacteria

Asian Sword Fern

Balsam-Pear

Boston Fern

Cowpea

Creeping Cucumber

Golden Polypody Fern

Grapes

Laurel Fig

Leafy liverworts

Lichens

Mosses of various species

Passionvines

Poison Ivy

Shoestring Fern usually with the moss Octoblepharum

Smilax

Strangler Fig

Tuberous Sword Fern

Virginia Creeper

Whisk-Fern (Psilotum)

 

Today’s primary source:  CLICK

 

 

Mud Dwellers are a Little Different

Nature abhors a vacuum, including  muddy shores freshly exposed by the seasonal retreat of erstwhile shallow ponds.  Exposed barrens spell opportunity for ambitious pioneer species.   Colonization happens fast.  To meet plants you otherwise seldom encounter, don your boots and don’t sink in chin-deep.

There are no pre-existing competitors on new mud.  All newcomers can stake a claim.  Nobody is competitively excluded, so diversity abounds.  Let’s see, in the postage stamp mudhole I explored today I recall seeing (running out of fingers and toes) over 20 plant species.

Seedlings rising with no competition yet.  The last owner of that marine seashell was probably 15,000 years ago.

Who’s first to settle?  Floating plants carpet the receding water and are the first settlers, although the species composition shifts substantially.   The pudding-dwellers arrive for the most part floating as whole plants, or as little breakaway pups, or as fragments, or as seeds or spores.  The mud community is far more diverse than the species readily spotted afloat.

Green lowlifes on smelly mud take me back 470 million years to when plants originally strode forth from water to land.  Standing on the mud today was a window into pre-pre-history.  Look who we find, at least two examples of the most primitive still-existing plants, liverworts, straight out of a museum diorama.   I’ll bet today’s liverworts are almost unchanged from the first terrestrial plants, not counting bacteria and algae.

Liverwort Riccia fluitans. Welcome to the time machine.  Bet it looked the same in the Ordovician Period.

Liverwort Riccia cavernosa.  Do the cavities facilitate gas exchange?  Any symbionts in there?   I’ve seen a lot of diatoms on/around this liverwort, but have no idea if that means anything.

The real fun is seeing who the castaways are and their adaptations to the mud world.  What are the facts of life on quicksand?  It is sopping wet, unless the sun bakes the surface dry.    The habitat is too suffocatingly soggy to invite extensive roots.    It smells like sulfur.   Nutrient acquisition must be a challenge.

At least one resident brings its own nutritional assistance.  The floating fern Azolla has folded into its leaves symbiotic nitrogen fixing Cyanobacteria, microbial fertilizer factories.   It can have all the nitrogen it wants.   The other floater in the photo below, Salvinia, has every third leaf modified into a big nutrient mop no doubt able to help with the fertilizer problem in its own fashion.

Floating ferns love this stuff!  Salvinia with the big hairs on the right.  Azolla is on the left, with its internal Cyanobacteria.

The next rain spells doomsday for these precarious species, although each is ready for rainageddon in its own way.  They arrived floating, and can depart the same way, no problem?  What about those who came by seed and need to make new seeds?  They work fast.  The Pentodon in the photo below can bloom and fruit while still mere baby seedlings, not a moment to waste.   After that safe start,  the longer they live the bigger and more fecund they can be.

Precocious Pentodon, flowering as a seedling.

The Ceratopteris ferns, water sprites, can float and make bulbils to disperse as clones, and even better, they mature from spores to reproducing adults in as little as three months to complete their sexual cycle.

Returning to seeds, one way to win a race is speed, as we just discussed, but there’s another way… a head start like the Nebraska Sooners.  Barnyard Grass, Echinochloa crus-galli,   jumps the gun by having the rare ability for its seeds to germinate in the absence of oxygen still submerged or buried in stinking mud.  That is why this grass is a pest in rice paddies.

Another response to re-rising water is to live with it. The Southern Marsh Yellow Cress, Rorippa teres,  sprouts all over the mud.  Not only does it flower and set seeds early in life, it can probably also live submerged if its relatives are a good measure.  Although I do not have data on this species per se, some of its close kin have survived and grown during underwater tests as long as three months.  Let it rain!

Rorippa

 

On Line Free South Florida Native Plants Course Registration

Free! (except for book purchase)

Register now.  Begins January 7,  2019

By John Bradford* and George Rogers

• 16 habitat-based lessons View the course at:
• www.nativeplantclass.weebly.com
• You’ll need our book: Guide to the Native Plants of Florida’s Treasure Coast by John Bradford and George Rogers.  To see the book, open Lesson 1, and click the link to the book vendor http://www.blurb.com. We make zero money from the book—any revenue supports our web site fees and printing costs, and nothing more.  Order now—delivery is slow.
• Grab a field companion.  For each habitat type you take a field trip on your own with camera in hand. We list suggested field sites on the course web site. Most habitats span multiple lessons, so you DO NOT need a field trip for each lesson.  Your cell phone camera is fine.
• The class evolved in Palm Beach and Martin counties. Students from anywhere are welcome, although the lessons are geographically biased.
• There’s a quiz each lesson, and three exams.
• The mission is learning to recognize wild plants. There is no attention to gardening, to landscaping, or to environmental issues.
• Certificates of completion will be available to successful completers.
• We proceed a lesson a week. We ask that participants keep up, although flexibility when “life intrudes” is the policy.   So feel free to take a trip or get the Plague.

To register or for more information George Rogers (rogersg515@gmail.com).    STOP!  BEFORE REGISTERING  read lesson 1 on www.nativeplantclass.weebly.com.   Make sure you know what you are getting into.   We’re not nice about people who register, take a seat, and then vanish!   If you are “in,” order the book with 3 weeks lead time.

Then send your name, e-mail, and cell number to George Rogers rogersg515@gmail.com or rogersg@palmbeachstate.edu.   Registration is first-come, first served.   You will receive a confirmation.

Why a free class? Merely good green fun.   We have no interest in quibbling or rudeness, and anybody who can’t help keep it pleasant will get the boot!    This on-line class is an open-enrollment public-access derivative of George Rogers’s “Plants of Florida Ecosystems” (ORH2511) taught on-line and in the field at Palm Beach State College in Palm Beach Gardens.

 *John Bradford, although a co-creator of the class materials, will not be available for the Spring 2019 session.  Don’t worry, he’s not having a problem, and yes we are getting along.  In Lesson 1 please note that instead of to John all assignments are sent to George this session.

 

What’s Cup Grass Have In Its Cup?

Eriochloa michauxii and related species

(Eriochloa is Latin for “woolly grass.”  Andre Michaux, 1746-1802, was a French  botanical explorer in the U.S., and elsewhere.)

Poaceae

A genus of grasses a treat to encounter around here, not that often, are the Cup Grasses, in the genus  Eriochloa.   Eriochloa michauxii is native, joined by a couple of uncommon non-native or marginal species in Florida.

Eriochloa michauxii by John Bradford

Overall, the genus is known for its adaptation to salty habitats, especially by possession of salt removal glands in some species, but that is not the main point of interest today.    Here’s the thing:

Why are they called “Cup Grasses”?

Each flower-fruit unit (spikelet) sits atop a little cup, like an egg in an egg cup.

And that being so, what good is that cup beyond helping with identification?

By JB

Botanists of yore thought the cup represented a modified leaf associated with grass spikelets (the lower glume), but no, the cup has emerged via fine research as an entity of its own,  curiously with a thin membrane around the rim.

Microscope view of the cup and its rim (red bar).  The spikelet (containing flower, fruit) is the big green speartip rising from the cup diagonally across the image.

A cup, especially one with a thin extra lip around the rim must hold something.  It does…bits of fatty material, lipids, the membrane edge probably protecting the greasy contents during the collection phase.  I’m not sure exactly where the lipids originate to wind up in the cup.   Either the chalice makes the fatty deposits, or they drop in from above.   In any case, the enriched cup falls away with the spikelet at dispersal time and seems to be a goodie basket for hungry ants enticed by a fatty  treat to drag the spikelet with benefits back to their nests, thus dispersing the grass species.

 

Middle Aged Meadows and the Middle-Loving Plants

I’ve always loved sunshine, butterflies, goldenrods, and fragrances in cheerful meadows evocative of childhood memories.

Meadows and butterflies, it’s only natural!

Attractive meadows in the Cypress Creek Natural Area near Jupiter, Florida, reflect several years of recovery after clearing and abandonment.   They represent a middle-successional stage.   Let me explain:

A textbook topic in Ecology is succession. Setting aside a couple controversies, the concept of ecological succession traces the history of a cleared area from its recolonization by annual pioneer weeds through a series of  plant communities onward and upward stepwise to a stable “climax” forest.      The stages and “final” outcome depend on the starting conditions, the basic habitat, and events.   The general trend with passing decades is from small and ephemeral toward large, heavy, and long-lived.

Today’s meadows represent a middle stage in succession.  A fairly predictable clique of species dominates such a mid-successional moist meadow.  What do the middlers have in common?    They are not just midway in successional time, but also in structure,  not exactly weeds,  pretty big, but not exactly hunky woody shrubs or trees either.   Tweeners adapted to life in the middle, just like 8^th graders in Middle School.

As succession begins the pioneer weedy species compete mostly simply to arrive, persist briefly, and disperse seeds.   But conditions change, becoming more crowded with the incoming  species being ever-taller and broader.  Mid-succession competition becomes a fight for the light, the winners rising above those who came before.    Then still later at the climax community the competition shifts again, to bearing  youngsters able to cope with the canopy shade.

Let’s go back to mid-succession and that contest to rise into the life-giving light.  The perennial weeds in our meadow are fairly tall:   goldenrods, musk-mints, and bluestem grasses as tall as I am.    The species able to surpass those perennials often are bare toward the base where the sun don’t shine,  the foliage held at 4-10 feet as required to overtop the big weeds.   Achieving comes to require some degree of woodiness.

Dog Fennell with bare “bamboo” stems lifting the foliage above competitors.

The “beginner” of woodiness is Dog Fennel,  often with stems resembling bamboo, even by having “tubular” construction the stem becoming a slightly woody cylinder around a soft pithy core.   The stems live just one season yet become just woody enough to carry the canopy aloft.   The perfect balance between “fast cheap expendable growth” and height.  It can’t decide if it is a pioneering weed or a woody shrub, a little of both.

Dog Fennell almost hollow.

Also dominant are Saltbushes.   Along with Dog Fennell they represent the Aster Family which is usually non-woody, yet these Baccharis species have just enough woodiness to stand up and fight.    Relevantly, biologist P.B. Tomlinson, in his “The Biology of Trees Native to Tropical Florida” noted how  despite having a woody trunk, Saltbushes “more resembles an herb.”  He observed further that, “most of the woody branches are short-lived so that older plants are characterized by a mass of dead twigs.”

Saltbush, alive up high, shedding dead branches down low.

That tendency toward dead twigs sounds like abandoning crowded older growth in favor of new growth where sunlight is plentiful.   Saltbushes are not alone in tending to go bare down low.   Slash Pines appear as saplings early in succession, growing with the successional stages.  As they rise, the pines have an early bare base, and then begin a lifelong habit of shedding lower branches.  Observers usually interpret this as protection from ground fires, but that does not rule out a secondary benefit of lifting the leafy crown above rising competitors (which could fuel a ground fire).

Another species sometimes prone to die down low  and  renew with tufts of leaves up high is Wax Myrtle, one of the dominant mid-successionists.   It and Saltbush have separate male and female individuals.

Wax Myrtle can dare to be bare below, with tufts above.

Wax Myrtle is one of the select few plants other than Legumes to have nitrogen-fixing root nodules,  giving it a competitive advantage on the terrible soils underlying the entire meadow.

On the Wax Myrtle root.

 

Cypress Twig Gall Midges Make Big Blue Galls

Taxodiomyia cupressiananassa

Cecidomyiidae

What family has the most species in the animal world?   Here is a contender, observers estimate up to a million species in the Gall Midge Family, with over 1000 named in North America alone.  They are micro-flies able to induce galls on plants as larval homes.   Many arthropods make galls, and today’s galls are the big waxy-blue eye-grabbers of the Cypress Twig Gall Midge.

Bald Cypress

John and I were working yesterday in the aptly named Cypress Creek Natural Area, walking along the edge of a compelling Bald Cypress population.  This species has the most intriguing quirks, for instance some of the most “ornamental” galls I’ve ever seen.  The galls can be numerous, on the  tips of its twigs, looking from the distance like some ripening fruit.  They are the work of the Cypress Twig Gall Midge (and maybe sometimes a second related species).  It decorates Bald Cypress, Pond Cypress, and the Montezuma Cypress native to Mexico.

The galls look like Juniper “Berries”

Members of the Gall Midge Family in a general sense can be pests and parasites on plant pests, that is, they can seem to protect their host tree, a benefit employed in horticulture for natural biocontrol.  I don’t know if the Cypress Twig Gall Midge (CTGM) bugs other pests, probably not, but it does suffer its own parasitoids…parasites on the parasite.    The structure of the gall therefore no doubt serves to protect the CTGM larvae cowering within from parasitoids, and from larger predators.

What is the gall’s structure?  It is soft, spongy, surprisingly large, to over an inch long, and coated with a blue-white powdery material suggestive of ripening fruit.   Larvae embedded in it may be nestled safely away from most parasitoids and predators.   But there could be more to the gall structure.

Gall opened.  There are many tiny midge larvae per gall.

And with that, we enter the speculation zone.  Beyond protecting the larvae, are there additional reasons why the galls are big, lightweight and spongy, and colorful?   How about helping to disperse the midges?   Not just storage…but moving and storage.

Bird Dispersal

The galls are the color of juniper “berries” and suggest bird-dispersed fruits.   I don’t know if birds peck them, but there a hint of plausibility hidden in a small literature on insect larvae dispersing via a bird’s gut.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1617192/

Dispersal could occur even if a bird merely pecks at the soft gall or rips part of it free and drops an uneaten fragment elsewhere.   The midges reportedly mate upon emerging from the gall, so a gall chunk with even two of the average reported 16 larvae per gall could relocate potential mates together.

Rodent Help

The galls occupy  the twig tips.  The twigs are deciduous, so the galls land on the ground. Rodents and ground-dwelling birds, even large insects, could move them or fragments hither and thither.

Floating Around

The galls bob like corks, remaining dry and waterproof.    The twigs and galls drop more or less during the relatively dry season, but then again, it does rain during their “on ground” time, some places such as creek banks have  water year-round, and we don’t know the entire temporal-spatial history of the galls anyhow.  Maybe that waxy coating has to do with flotation,  water-proofing, and decay delay.

Final Mystery

As a closing note,  biologists George Washburn and Sunshine Bael last year found a connection between midge success and fungal diversity within the gall.  The galls are little fungus gardens.   Who knows why? Do the fungi help sustain or protect the midges?   Or do midge larvae in the gall promote fungi? Or both?  Neither?  Are larger galls merely better habitats for larvae and fungi?  Does the mother midge inject fungi during oviposition, and if so, why?