You Can’t Keep a Good Fern Down

Small Leaf Climbing Fern

Lygodium microphyllum

(Lygodium means flexible. Microphyllum means small leaf)

Schizaeaceae

 

This morning John and I pursued minor projects in Kiplinger Wildlife Preserve, in awe of the imperialistic Small Leaf Climbing Fern,  a gift that keeps on giving from the Old World, first recorded in Florida during Elvis, escaped during the Beatles.

Going up!   By John Bradford.

Its massive growth is matched by  massive attention to its peskiness on the Internet. No need to be the millionth post on that.  For those unfamiliar with the problem, probably not Florida residents, this fern can smother a tree in the wink of an eye, climb high into the canopy, spread fires, and even reportedly snare a deer.

Spore-bearing leaflets. By JB

Rather than rant on about invasiveness, it might be more interesting to explore the biology of this super-weed.  Two invasive Lygodiums compete to own Florida:  Lygodium microphyllum is  common around Palm Beach County.  Lygodium japonicum is more prevalent northward.   Farther north still across the Florida state line comes the native Lygodium palmatum.  The invasive species grow like lightning, L japonicum as much as three inches a day.

Leaflets along a small stretch of one long rising leaf.

These clambering vines are not really vines.  The entire aboveground  climber is a leaf, a frond, although division into leaflets along a stringy center gives the false appearance of a leafy stem.    But no.  The true stem is at or below ground level,  launching the immortal ever-lengthening leaves skyward to go forth and multiply.    The individual leaves climb 30 feet or more.

And here is how:    The tip of most any fern leaf (frond) is a curl called a crozier.   Normally the crozier uncurls, and that’s that.  But this is no normal fern.  In Lygodium the crozier never uncurls.  It just keeps on lengthening the leaf.    The leaf portion behind the crozier stays bare like a thin twig and forms a hook.  The hook rotates on its own, and also blows in the wind.   All this twistin’, and hookin’; and blowin’ is an effort to hook onto something to climb.   When that happens, let the rise ensue until the leaf snakes to the top of the host, then the hooky business resumes seeking a taller host.  Upsie daisy!  Below the hooky region the older regions broaden out into the characteristic leaflets,  hundreds of them like lights bulbs strung on a wire around a used car lot.

Climbing Fern crozier

If a leaf extends high up into the tree and then breaks off, oh my, what a disaster.  But no, wait, there is a safety mechanism.  Along the leaf are fuzzy rust-colored buds ready to grow forth and save the day.

That the leaves rise directly from the “roots” allows direct immediate nutrient interchange between leaf and “root.”   Such efficient root-leaf commerce has turned out, it seems, to allow for especially enriched roots to cope with bad soil, not to mention fuel that magical leaf growth.

Hooked leaf tip, crozier at the very end.

Botanists have shown…at least under some circumstances…the plants to grow equally well in bright sun and deep shade.  They do not care.   Wet places are favorite habitats, pine woods will do, and even sometimes dry scrub.    It’s all good!   Flooding seems to boost spore production, and that is a deliberate segue:

Ferns reproduce by dust-sized spores blowing in the wind.  One individual Climbing Fern can produce astronomical numbers of spores.  There has been concern that workers exterminating the fern get their clothes contaminated with spores, spreading the pest unwittingly, helping it rather than wiping it out.

Fuzzy bud on leaf.

Watch the hook helped by wind seek a new host to climb:   CLICK

When the baby Climbing Fern  grows from the spore it matures as female with a trick. She releases hormones to make the  nearby babies mature male as automatic mates.

If that fails, the female develops its own sperm-producing organs and fertilizers itself.

There’s no stopping Climbing Fern.

Photo courtesy of John Lampkin.

 

Ornithocoprophily, A Bacterial Surprise, and Hungry Bunnies

Silvilagus palustris

Leporidae

 

After serial thwarts the last couple Fridays, John and George finally hit the muddy road today, mostly to think big— to shoot broad-perspective video of a marsh in the Kiplinger Nature Preserve for a project evolving under John’s  video genius.    (We’ll return to that in due course.)  Thinking big shifts the focus from wildflowers to the forest.

In a Florida marsh, an obvious fact from a distance is that our feathered friends prefer certain trees for roosting and more.    And if birds occupy an individual tree or clump much of the time,  guano showers below.    Fertilizer!  On Florida’s otherwise awful, nutrient-poor, sandy soil.  That’s gotta matter!

To go to the extreme case, consider “tree islands” with rookeries.   Biologist Paul Wetzel and collaborators in 2005 reviewed the relationship between rookeries and Florida tree islands, with points to ponder.   Although bird manure is not the only source of phosphorus enrichment in a “tree island,”  it can account for 20 times that from other sources, and 3000 times that from atmospheric fallout.  Such super-fertilization can generate “luxuriant” growth persisting up to 50 years thereafter, although the overall effects on species composition need attention.  In smaller venues with lower levels of deposition the floristic effects need study.  What I really want to know if the main broadleaf tree of the Everglades and a beloved roosting tree,  Pond-Apple, which is prominent in Kiplinger,  practices ornithocoprophily (love for bird dung).

What bird dung does.  (From Wetzel et al.  Front. Ecol. Enviro. 2005.)

 

Tree fertilization technicians at work:  PECK HERE

While still up in those well fed trees, look at one of the commonest pants there, Ball-Moss.    Not really a moss, this species is Tillandsia recurvata, an epiphytic Bromeliad and relative of similar Spanish-Moss.

Ball-Moss in a tree, by John Bradford

To see Ball-Moss go peek up any oak tree, or even a telephone wire.   This little airplant thrives up high clinging to twigs where soil nutrients are not.   The species captures rainwater under beautiful microscopic leaf scales.  All good, but is that enough for “fertilizer”?

Scale from Spanish-Moss, close relative of Ball-Moss. (Courtesy of Dr. Robert Wise, UW Oshkosh)

Back in 1994 ecologists M.E. Puente and Y. Bashan didn’t think so, and uncovered a surprise:  nitrogen-fixing bacteria haunting the tissues of Ball-Moss.  Nitrogen fixation is the process of converting inert nitrogen gas from the air into ammonium a plant can use.    This is most famously the domain of legumes with their own bacteria, but more and more non-legumes with nitrogen-fixing powers are turning up.   The bacterium in the Ball-Moss is Pseudomonas stutzeri, which would be nothing but anther boring Latin name except for two things:

Thing 1. The same bacterium has surfaced as a nitrogen fixer in a grass.

Thing 2. The same germ is a minor human pathogen. CLICK FOR DETAILS

Oh no, does that mean handling Ball-Moss exposes a person to potentially deadly bacteria?    Technically, yes.  In practice, I have no idea.  But in any case it underscores the little hobgoblins lurking in the weeds around us.

The bacteria feed the Ball-Moss, and the Ball-Moss helps this rascal with dietary fiber. ONE FINAL CLICK

 

 

 

Carolina Ash, Pop Ash

Fraxinus caroliniana

(Fraxinus is an ancient name for ash trees.  Caroliniana is self-explanatory.)

Oleaceae (Olive Family)

 

If you live in Florida and become nostalgic for woods with a “northern feel,” go to the shore of a river and get among species of ash, hickory, jack in the pulpit,  maples, and more.  Feels like Ohio.  Even a little fall color from all the poison ivy.   I always take special pleasure in coming upon Carolina Ash, so much so I invited  one into my yard where it has become a pretty shade tree.

Carolina Ash leaves and samaras.   Photos by John Bradford.

Any ash-fancier must dread the exotic Emerald Ash Borer beetle destroying thousands of ashes in northern states.   The pest is expanding southward, and Carolina Ash is likely susceptible along with our other species.  So far so good in Florida.

The trees are separately male and female with tiny non-showy wind-pollinated flowers.   As with most wind-pollinated trees, the species is deciduous.  They do not seem at first glance to fit in the Olive Family, as olives have pretty white insect-pollinated flowers and big fleshy fruits.     But if you had a magic transformer wand you could morph an olive into an ash.  All the fundamentals remain the same, just with different points of emphasis.     In fact, there are missing links, including a species of “Flowering Ash” with showy white flowers, and several species where the two sexes have not split into separate individuals.     The most interesting link is olive oil.    Everybody knows olive oil, but I’ll bet Rachel Ray never tried extra virgin ash oil.    In some places edible oil is squeezed from ash seeds, which otherwise have little resemblance to an olive beyond the oil and a single seed.

Ash fruits look like an olive run over by a steamroller.   The fruits are smashed flat into an elongate green wing with a seed embedded at one end.     Such winged fruits are properly termed samaras, a great name for a sailboat.     The party line in every botany textbook is that “the” function of a samara is to flutter away on the wind  to scater the seeds.    OK, we can stipulate to that, but could there be more to it?

Various botanists over the years have suggested that the big flat green wing helps feed the embryo embedded in it.   Samara wings have been shown to photosynthesize, and thus serve as a solar baby-food makers intimately attached to the baby.  As a subjective observation, the samara veins look like feeding network leading straight to the seed.  Although sporadically discussed and obviously plausible,  the Gerber Hypothesis could use a measure of  hard-data research.  Then the question must be addressed,  and if sustained, does the samara feed the baby even after dropping from the parent tree?

 

Indian-Hemp

Sida rhombifolia

(Sida is an ancient name for a different plant.  Rhombifolia describes the leaf shape.)

Malvaceae (Hibiscus Family)

 

Once upon a time, before the era of polyester leisure suits, natural fibers ruled, and Florida was a place to research and grow fiber-bearing species.    Fiber plant importation here predates the European invasion probably, as our “native” Florida agaves arrived it seems at the hand of prehistoric people no doubt to supply strings, hammocks, and fishing nets.    Florida’s first prominent Euro-horticulturist Dr. Henry Perrine introduced more agaves, most notably sisal, now an invasive exotic species.  Dr. Perrine perished by homicide before Florida fiber fun hits it prime.

Caesarweed, a fiber species.   Today’s flower photos by John Bradford.

Fiber species are mainly tropical, and the Sunshine State was home to avid 19^th and 20^th Century plant introducers.    It is tough to cite the exact time, purpose, and unsub in a plant introduction, so to keep it general, let’s just say some species came to Florida as dental floss.   And, yes, fiber plants have served oral hygiene where there’s no Walgreens on every corner.

An incomplete list of fiber species still in Florida follows:

Bowstring-Hemp (Sansevierias, the “Snake Plants” in pots and gardens, breeders used to hybridize Sansevierias  in search of fabulous fibers)

Caesarweed (Urena lobata, now it sticks burrs on our shirts)

Flax (Linum usitatissimum, also giving seeds to muffins)

Hemp (same species as ganja)

Indian-Hemp (not really a hemp)

Jute (Corchorus species,  gunny sacks and upscale couture)

Kenaf (Hibiscus cannabinus, save the forest, farm paper)

Manila-Hemp (Musa textilis, a banana of all things)

Ramie (Boehmeria nivea, related to the native false nettle)

Sisal (Agave sisalana, and other Agave species)

Yucca (Yucca species)

This photo published 1893

There are more but lists are for losers, so to get to today’s hot topic:

Indian-Hemp

Indian-Hemp is a classification mess, in a complex of variants you may or may not interpret as separate species.    Native to Florida?  Some say yes, but my favorite general reference, Flora North America, calls it an introduction from the Old World, and I’d not quibble.  Importation from India gave Indian-Hemp its name.  If you want to see Indian-Hemp in Florida, take a walk.  An encounter will likely ensue.

Indian-Hemp fibers

Every plant species has history in human medicine…it gets boring…but we have finally found the species applied by somebody somewhere to counter every known ailment, from alopecia to zits.  And for those itching to boil and gobble the world of green, be careful, today’s species reportedly causes abortion among other damages.   The species also induces vomiting, but contemporary politics is more effective for that.   All in all, Sidas are chock full of drugs and stuff, with one ingredient especially interesting…ephedrine.

The stimulant ephedrine crops up in human medications, legally and not so much.     By far the best- known botanical source is the genus Ephedra, very weird desert plants having seeds but no flowers, giving the “kick” in Mormon-Tea as well as to the Chinese beverage ma huang, not to mention diet pills, inhalers, and much more.  Ephedra is about as unrelated to Sida as possible, so what the heck is ephedrine doing in our backyard fiber weed?   In any case, smoking Indian-Hemp is a reported use…obviously a nitwit idea.  I wonder if ephedrine or similar alkaloids are behind that dangerous passtime.

To wrap it up with a curiosity, the fruit starts out looking like a pie.  And it winds up with the same fate, sliced into triangular segments, each acting like a separate fruit,  out of one, many.     Sometimes triangular  flower parts (sepals) wrap around the pie from below,  embracing the pie and holding its slices in place.   Although an obvious possibility, I can’t say for sure the embrace is a function of the weather. Today was rainy and gray, and the grip was tight, however.

The fruit with the pie slices hidden by the triangular flaps bent up from below.

Protective flaps bent back, and the pie slices exposed.

 

 

 

 

 

Elliott’s Milkpea Basking in Climate Change

Galactia elliottii

(Galactia refers to milky stems on one species.  Botanist Stephen Elliott lived in Beaufort, SC, where he was first to collect this species.)

Fabaceae (Legumes)

Today’s visit to the Kiplinger Nature Preserve in Stuart, Florida, saw the first big blooming loblolly bay flowers of the season, a relative of tea and camellias featured some time ago in this blog.

Loblolly Bay, by John Bradford.  All flower photos today by John.

Today is Wednesday, not the usual Friday trip, due to travel plans. Crabs were crab-walking all about, and a black racer popped up for a peep at us.

This was white-flower day, with the loblolly bays,  tarflower, pineland asters, and the plant of the day, Elliott’s Milkpea.

It seems to be designed perfectly for where it lives:   largely in pine flatwoods and scrub.  In short, it has to live conditions ranging from sunny to shady,  where fires pass by,  where water is intermittent, and  where the world’s poorest soils strive to stifle growth.  The plants possess extremely log underground runners,  a rapidly growing twining stem able to sprawl, spread and climb over the ground and over shrubby companions,  tolerance for shade or sun alike, and leaves with adjustable positions.    The most noteworthy and most-studied adaptation is its nitrogen-fixing root nodules.

Although most legume roots “fix” nitrogen, that is, extract it with bacterial help from the air and transform it into fertilizer,  this skill seems to matter especially in the sterile world where Elliott’s Milkpea holds forth.     Nitrogen is scanty in the sterile leached white sand of scrub, where much nitrogen fixation is the work of microbes in the surface crust.      Pine flatwoods soil is sterile too…sandy,  often poorly drained,  and with a dark layer that presumably blocks nutrient exchange.

For reasons such as these, Elliott’s Milkpea has become a guinea pig for ecologists asking questions concerning the effects of rising carbon dioxide concentrations.     Closely related is the relationship of rising carbon dioxide to  nitrogen fixation, and what better test subject than a vigorous pea living in a natural sand box?

Nitrogen fixation and carbon (dioxide) have a direct link.    The symbiotic nitrogen-fixing bacteria are paid in carbon for their ammonia fertilizer a swap.   So then, a plant using carbon to buy nitrogen might enjoy a boost if given more carbon to trade.    Biologist B.A. Hungate at Northern Arizona University and collaborators studied today’s species exposed to artificially high carbon dioxide over several years.      At first, elevated carbon dioxide boosted nitrogen fixation, presumably an advantage to the pea plants and thus potentially capable of messing with species balance.   After approximately a year, however, the boost disappeared, probably because, especially in awful soil, resources other than carbon and nitrogen became limiting.   I might make my car go faster by putting the pedal to the metal, until an empty gas tank (or a state trooper) become limiting.  What runs low, according to researchers, might be the element molybdenum.

 

 

Spanish Needles, Beggarticks

Bidens pilosa

(including populations traditionally called Bidens alba)

(Bidens means two teeth. Pilosa refers to hairiness.)

Asteraceae

 

Wildlife was abundant today in the Kiplinger Natural Preserve where John and I greeted a friendly osprey, fiddler crabs waving their fiddles in the mangrove mud,  a young land crab posing as a giant spider, and a photogenic corn snake too quick for photos.

Got eggs?

Anyone who knows me knows that I find the rare attributes of common species far more interesting than roaming to see rare species.  It takes work to know the species literally in our own back yards, including Kiplinger.   You couldn’t have a commoner weed than Spanish Needles; they are everywhere, and the yellow and white flower heads decorated the trails (and our socks) today.

Spanish Needles by John Bradford

We all know this species, if not as a wildflower, at least as the source of sticktights in our shoelaces and pants cuffs.  They have been known to disperse in the clothes dryer from the trousers of an innocent botanist to his spouse’s apparel, eliciting muttering.  The stickers are well designed, a pair of barbed devil horns on the tip of the seedlike fruit.

Ouch

The fruits of this and some other members of the Aster Family have a second oddity, studied in depth by botanist O.J. Rocha in the mid 90s.  It is something you can see easily while walking the dog.   The headlike fruit cluster has two different types of fruits, or intergrading extremes.   Those at the center of the cluster are longer (let’s call them the central fruits) than those toward the edge of the cluster (edge fruits).

Cluster of fruits.  The central fruits are larger than the edge fruits (small one in circle).

The two fruit types have different jobs. The long central fruits  germinate quickly, and are more quickly relocated away from the mother plant.   Their job is to get far away, and spread the species now.

Older fruit clusters.  The central fruits are disappearing.  The edge fruits remain.

By contrast, the edge fruits are reluctant to germinate, probably resist taking in water,  tend to require light to sprout, and cling to the mother plant.     Their job is to repopulate the home site eventually, persisting for who knows how long in the soil waiting for the prior generation to perish and open new opportunity.  Their requirement for light is apparently the cue that the parents have vacated. It would be fun and easy to compare the longevity of the two different fruit types buried in the soil.

Ever notice how Spanish Needles always look free of insect damage, even when the plants around are in tatters?   The species is a witch’s brew of toxins, including poisons researched as potentially destructive to human tumor cells.  One ingredient is PHT (phenylheptatriyne).   PHT smites your foes by destroying membranes.  Everything has membranes so the effect is broad spectrum, beating down such enemies as membrane-bound viruses, bacteria, insect pests, probably us, and competing vegetation.  Contrary to advice by those who feel the most interesting thing about wild plants is eating them…a penchant I’ve never fathomed…just fuggedaboutit!  Unless you are the dainty sulfur butterfly using today’s species as larval host.

By JB

 

Dragonflies and Plants

Travel plans prevent a Friday fieldtrip this week, so a preemptive strike now a day early.    This week there are dragonflies in the skies, lots of them.    Halloween Pennants. So enchanting, so acrobatic,  and so molested by all our water pollution and its consequences, but no soapbox here.  Keep it fun.

Halloween Pennant.  All still photos today by John Bradford.

Today the mission is to connect dragonflies with plants.   The first obvious thought then is, “do they pollinate flowers?”   Not an unnatural notion  given all the marsh plants with flowers on top, just where dragonflies perch.   Although dragonflies are not often credited with pollination benefits,  the late Dr. Peter Yeo,  go-to botanist for pollination,  suspected dragonflies as likely pollinators for some Xyris.   I’d be an easy sell on that.

Xyris

Even though dragonflies probably don’t deliver much pollen, they will not be denied a role in flower biology.   As anti-pollinators!  Dragonflies are wicked predators while as larvae in the water and as adult insect-gobbling attack copters.    A couple studies over the years have shown dragonflies to reduce pollinator populations sometimes enough to matter.    Not really a “bad” thing, merely a hand in the balance of nature.

A third impact for dragonflies on plants is more subtle.    The big lugs move nutrients from aquatic ecosystems outward to terrestrial systems.  This might add up to significance, given the abundances, sizes, and appetites of dragonflies,  transferring nutrients from their aquatic cradle to wherever they perish, perhaps during massive migrations, or possibly as a bird snack, and along the way, devouring and spreading the remains of insect prey.    Dragonflies can live multiple months.

Humans can benefit from, even use, the insecto-destruction powers of dragonflies.  They are valued pest control agents in rice paddies, and have been contracted to help control Zeka-bearing mosquitoes. A small number of dragonfly larvae can remove a lot of mosquito larvae from their watery beginnings.

For a wacky interspecific collusion, consider related damselflies whose submarine larva positions itself to promote photosynthesis by algae (Euglenoids) within the flesh of the larva, the larva benefiting from the oxygen the algae emit.

Dragonflies are territorial, although I think you’d have to be one to understand their social signals during short missions darting around interspersed with restful moments perching, then sometimes visibly munching their victims.   As a dragonfly watcher, I have stumbled into a mystery:   leg-waving, encountered repeatedly.     Why a perched dragonfly might wave a leg could be anything from a social signal (my guess) to itchy toes.   If anybody really knows why, the truth has escaped me…and I’ve tried to find out.  Watch the wave in the video below, and make a guess.

FLIT HERE to see dragonfly action!