Thursday, January 5, 2017

2016 Geology Posts and Photos That Never Quite Made It

A "Worm Rock" from the Middle Holocene; A Little Swamp Geology; Geological Torture in the Grapevines; Ubiquitous and (Almost) Forgotten Brick (and Clay); The Many Marbled Monument to George; Finding "Needle Ice" on Little Haystack; Persistent "Fairy Rings" of Late Summer   

What shall I post about next? Is the subject matter worthy of discussion? What shall I say? What shall I omit? It’s the blogger’s never-ending dilemma. By the time the end of the year rolls around, at least for me, there are always a few posts that never got written and a few images that never got uploaded. And so, with this final post of the year – in what has been a tradition on my blog for five years running – here’s my end-of-the year post (although a little belated). Please visit the same for 2012 (here), 2013 (here), 2014 (here) and 2015 (here).

January
 A “Worm Rock” from the Middle Holocene
Naples Beach, Southwest Coastal Florida


In spite of the fact that Southern Florida is almost virtually flat and hasn't experienced any significant form of tectonic deformation since it "emerged from the sea" some 25 million years ago, it has a fascinating geologic history (here). But with a paucity of telltale outcrops, no hills to speak of let alone mountains, no roadcuts or readily accessible quarries, doing geology is a challenge.

So, while on vacation with clear blue skies and 1,350 miles of accessible coastline, it seemed logical to head to the beach and see what the tide had brought in. To my surprise, I discovered a fossil remnant of a unique, marine bivalve colony that is responsible for the geomorphology of southwest Florida's carbonate-producing coastline and offshore islands. 


How am I going to do any geology here?

Southeast of Marco Island along the southwest coast of Florida is the archipelago of Ten Thousand Islands. It’s a maze of oyster shoals, mangrove trees and brackish tidal channels that are a few miles wide and up to 20 miles long. The islands are actually part of an interesting stratal sequence deposited some 7,000 to 3,000 years ago. 

Following the Pleistocene ice age, Holocene transgressions began to flood the Florida shelf. A basal peat layer formed below sea level that overlies eroded Pliocene and Pleistocene limestones. Quartz and shelly sands followed as the sea level rose. Overlying the sands of the inner islands are Holocene-age oyster reef beds that are overlain by modern peat and support the region’s mangroves. The right conditions of rising seas, climate and sedimentation converged over this interval to promote reef development.


Extant Vermetid Marine Gastropod Serpulorbis squamigerus
Rather than having regularly coiled shells, the elongated tubular shells of vermetid worm snails grow on hard surfaces either solitary or cemented together. The adult or apertural end portion of the shell is free and directed upward.
From Wikipedia

The outer islands, in addition to oyster beds, have an up to 10 foot-layer of the worm-like mollusk Petalochonchus varians. The marine gastropod is of the Vermetidae family but doesn’t resemble the coiled shell of the average sea snail and is frequently interpreted as a marine annelid, tube worm, and vice versa. The "worm snails” grow cemented together in complex, anastomosing colonies locally known as “worm rocks.” From about 3,000 years ago, they formed a small barrier reef system until recently, when they began to experience an inexplicable global decline. On occasion, dislodged erratics wash ashore and await discovery by unsuspecting geo-beachcomers.

January
A Little Swamp Geology
 Big Cypress National Preserve, Southern Florida

An Alligator-infested Open Strand in Big Cypress Preserve Surrounded by Cypress and Deciduous Hardwood Trees

The foundation of the Florida Everglades and Big Cypress Preserve is essentially a limestone-based, former ocean bottom. The Everglades fills the 4,000 sq mi expanse between Miami on the Atlantic Coast and Naples on the Gulf Coast and resides in a shallow geological basin or paleo-trough confined by the topographically low (a maximum of eight feet above sea level) and narrow Atlantic Coastal Ridge on the east. 

Water lazily flows to the south and southwest at a barely perceptible rate since the landscape is almost virtually flat - only two inches per mile! As a result, it is subject to extraordinary extremes of wet and dry weather. Far more than just a stagnant pool with a high watertable, the “River of Grass” is a wide, slowly moving, freshwater sawgrass prairie or marsh. "Sheet-flow" is the frequently used, descriptive term.

Southern Florida's hyrologic ecosystem includes the Everglades, Big Cypress and Ten Thousand islands

The Everglades system is no longer a single hydrologic unit. For purposes of flood control, agricultural irrigation, habitable real estate and fresh water, its natural flow has been re-engineered into a "water management system" that has been compartmentalized, fragmented and sub-sectioned with a network of canals, flood gates, levees and highways that criss-cross and subdivide it. It's a nutrient-poor ecosystem supplied by rainfall and plant decay, which over eons has created a stratum of peat in depressed areas. But now, it's in a state of nutrient overload from fertilizer that has drifted downstream from the agriculture district below Okeechobee and from both animal and human waste. The result is a stressed, altered and unsustainable ecosystem without natural flow. 

West and southwest of the Everglades and confined by the limestone Immokalee Rise lies the state's other major wetland, the 1,200 sq mi swamp of Big Cypress. Eastern America's "last great wilderness" is named for its area rather than the size of its flood-adapted, deciduous trees. It's actually an extension of the Everglades hydrologic system. The two are integrally-related and similarly nutrient-poor, but their character, biology, ecology and geology are surprisingly quite different. 


Over half of the Big Cypress Preserve is a cypress swamp, but its includes open stands of small cypress trees that grow seasonally among seasonally-flooded grasslands known as cypress prairie. Another quarter is comprised of various forms of treeless wet prairies and marshes, while some 15% supports pine forests, less than 4% is elevated enough to support upland hardwood forests and around 1% extends into the mangrove zone along Florida's southwest coast. Exotic invasive plants (such the Australian tree melaleuca was introduced in the early 1900's as an ornamental and lumbar source) live within the preserve that often place native species in peril by competition. The same holds true for native sawgrass in the Everglades and fauna such as the Burmese python. Can you spot the alligator lying in wait?



In common, they occupy one of the lowest, youngest and most geologically stable platforms in North America. And like the Everglades, due to its low topography, Big Cypress has repeatedly been submerged and exposed by the sea within the last 50,000 years. But, the bedrock beneath Big Cypress - thousands of feet of carbonate strata - is harder and less porous, which is reflected in the growth conditions of the vegetation, although, like the Everglades, it can store a great deal of water.  


The Swamp Lily or String Lilly (Crinum americanum) is actually an Amaryllis.

Reduced drainage into the underlying rock during the dry season in the Everglades promotes periodic soil fires, which are actually beneficial and no longer extinguished (and even prescribed), since it releases nutrients back to the soil and promotes biological diversity. It is lethal to cypress with the exception of their resistant above-ground portions. Big Cypress bedrock is more protective of the vegetation. Water is from direct rainfall without significant contributing flow from the north in contrast to the Everglades that is fed from the vast and shallow headwaters of Lake Okeechobee.


Big Cypress's Majestic, Swamp-loving Wading Bird, the Great Blue Heron (Ardea herodias


Water outflow from Big Cypress is eastward to the southernmost Everglades but also westward into the mangrove swamps and the Ten Thousand Islands coastal region on the Gulf of Mexico that serves as a buffer between the salty sea and freshwater marsh. For information on the geological evolution of the Florida Platform, please visit my post here.


February
Geological Torture in the Grapevines
Lost Valley and Titus Canyon, Death Valley National Park

Looking NNW into Lost Valley From Red Pass Towards Leadfield and Titus Canyon
Enter the following coordinates into an online mapping program such as Google Earth,
and it will take you there: 36°49' 44.12"N, 117°02'03.21"W.

Geological torture and Death Valley are synonymous. A good example is at "Lost Valley" or "Canyon" below Red Pass at 5,250 feet in the Grapevine Mountains on Death Valley’s northeast side. The landscape has seen it all - twisting, gnarling, folding, faulting, extension and compression. The "Bloody Pass" lies midway on a spectacular, 26-mile, single lane, high clearance drive westward from Amargosa Valley on the east to Death Valley that finishes with a climactic drive through narrow Titus Canyon. The excursion is a complicated exercise in structural and stratigraphic geo-gymnastics.

The strata of Lost Valley spans time frames from Cambrian to Recent and represents continental clastic sedimentary rocks deposited on the miogeosyncline of western Laurentia (the rifted passive margin of the supercontinent of Rodinia), ash flow tuffs (the products of volcanic eruptions related to the middle Miocene multi-calderic southwest Nevada volcanic field) and lavas (Miocene to Pliocene in age). Multi-colored conglomerates and sandstones in the walls belong to the Eocene to Oligocene Titus Canyon Formation. Alluvial fan and lacustrine deposits, megabreccias and conglomerates were deposited within a fault-controlled basin and provide evidence for Early Oligocene extension before the formation of Death Valley. Banded grays are mostly limestones of the Cambrian Bonanza King Formation, while beyond are volcanics.


The Upper Narrows of Titus Canyon
Geologist, author and guide Wayne Ranney (here) takes in the solitude and shade of the wider, upper narrows of Titus Canyon. Water (and the rocks and boulders that it carries) funneled down from the watershed of Lost Valley are responsible for the erosive-genesis of this otherwise bone-dry canyon. It's a commentary on the tremendous carving capacity of stream cutting in association with tributary erosion and mass wasting. But in what time frame? Geologists estimate that a 1-inch rainfall over the region's 35 square-mile watershed can excavate a few hundred thousand cubic feet of material in merely 50,000 years to create the massive fans that radiate outward from the canyon's mouth at Death Valley, not far from this point. Of course, these are arid times, and don't take into account the wetter post-Pleistocene climate that came before.

Haven't seen enough torture? Beyond Red Pass the road drops some 1,100 feet. Beyond the region of the notorious Leadfield mining district and ghost town, it almost abruptly enters the narrows (the reason the excursion is one-way) of 8.8 mile-long, rugged and cliff-walled Titus Canyon, named after a mining engineer that mysteriously perished in these parts back in 1905. A low-angle, normal fault dominates the structural framework of the canyon, which places younger strata above the fault in association with older rocks below the fault. On close inspection, the bedding appears to be horizontal and undeformed, but don't be fooled. A "big picture" stratigraphic and structural analysis will indicate that it is over-turned!


Counterintuitively, a drive down Titus Canyon takes you topographically downward into progressively younger rocks. It's because the strata has been inverted within a folded anticline.

One distinctive canyon wall is a massive mosaic of erosion-polished, brecciated (angular, flat-sided) dark carbonate fragments of the Middle Cambrian to early Late Cambrian Bonanza King Formation. It was deposited offshore - as was the familiar and geo-equivalent Middle Cambrian Muav Limestone of the Grand Canyon to the east - on the passive margin of Laurentia subsequent to the fragmentation of the supercontinent of Rodinia. How did the "mosaic" form? Analyze it a minute before you answer.


Dee and the Enigmatic Jigsaw Puzzle Wall of Titus Canyon

Here's one explanation. The white rock is crystalline calcite that lacks bedding planes and appears to hold Bonanza King fragments in suspension. It's a clue as to how the carbonate matrix formed. In addition, small lenses or tongues of calcite penetrate the Bonanza fragments, which almost fit together like the pieces of a puzzle. There are no obvious faults here. Therefore, the breccia is likely not a product of faulting but progressive fracturing. 

The mosaic may have formed under severe stress, deep underground and concurrent with the formation of an anitformal recumbent syncline (large-dimensional folds that are younger at the core and lie on their side). The host rock, the Bonanza King, fractured along with the intrusion of the molten, now flowable calcite that was derived by pressure solution of the host rock. Proof of recumbency is that older formations lie above younger ones. What's your interpretation?

April
Ubiquitous and (Almost) Forgotten Brick (and Clay)
Financial District of Boston

A Collage of Building Materials and Architectural Styles in the Financial District of Boston

The modern metropolis of Boston was built from a variety of local, regional and imported rock and stone assembled in every architectural style imaginable. Examples used in early construction include Late Proterozoic slates and conglomerates of Cambridge Argillite and Roxbury Conglomerate from the Boston Basin, middle Paleozoic granites from nearby Chelmsford, Quincy, Milford, Rockport and Stony Creek, early Mesozoic Portland brownstones from Connecticut's Hartford Basin and New Jersey's Newark Basin, and early Paleozoic marbles from Lee in Vermont. It’s easy to overlook the role that common brick has played in the growth of the city and New England. It's a ceramic structural material with main ingredients that arose from the weathering of igneous rocks and brought together by Pleistocene glacial depositional processes.

Take a drive through any town of considerable size in New England situated on a river that powered its mills in the nineteenth century. Even where building stone was available, the buildings are all composed of brick for reasons of economy and speed of construction. Things changed for brick at the turn of the twentieth century when the demand for high office buildings and less susceptibility to earthquakes increased, resulting in the use of cast and wrought iron, and later, steel and concrete. As for the mills, they closed in New England when alternatives to water power were developed and textile production became more profitable in southern states where cotton was grown and winters were warmer.


Postcard of the Brick-built Mill Town of Manchester, NH, on the Merrimack River

The first Europeans to arrive in New England needed brick for the chimneys of log cabins, which were built of stone plastered with lime made from the endless supply of crushed clam shells. Much needed New England timber was shipped to England, which required stone as a ballast in the empty holds on the return sail. Legend has it that river cobbles were used that were repurposed as street pavers. But, apparently “ballast” brick was substituted, found throughout New England in Period fireplaces, chimneys, street and sidewalk pavers, and foundations. Before long, as the demand rose, the colony’s growing population sought out local sources of clay for brickmaking, as kilns began to fire up everywhere. In New England, the first brick kiln was erected in the town of Salem, Massachusetts, in 1629.

Colonial Brick Buildings, Sidewalk-lined, and Cobble-paved Acorn Street in Boston's Beacon Hill
Although cobblestones were noisy under hooves and wagons in the old city, the cobbled streets didn't succumb to the degradative effects of long New England winters and remained mud free. Eventually they fell out of favor to rectangular granite setts in the 1800's and asphalt in the 1900's.

Clay is an essential ingredient in brick that happens to be extremely plentiful in New England. During the Pleistocene the Laurentide continental ice sheet made multiple advances and retreats over northern North America. Glacial scraping and gouging of the landscape began to end some 20,000 when the climate warmed, and it made a final retreat bringing the northeast into its current interglacial period. Erosional and depositional glacial features littered the landscape in the form of outwash (well-sorted and well drained sand and gravel) and till (an unsorted, non-stratified mix of clay, sand, silt, pebbles cobbles and boulders). 

Typical Gray to Greenish New England Glaciolacustrine Clay Pit
Wikimedia Commons

Clay was typically excavated from clay pits that formed at the bottom of the many post-glacial lakes that dot the landscape, delivered and sorted by glacial rivers and streams. The glacio-lacustrine deposit has a particle size smaller than 2 µm (which differentiates it from silt) and is defined as a fine-grained rock or soil combined with organic matter and certain minerals that form in the presence of water (commonly hydrous aluminum phyllosilicates and various metallic oxides such as iron and magnesium). Its silicate composition is a result of weathering of the glacially-scoured, granitic bedrock commonly found in upper New England. If clay remains in the soil long enough and is subjected to sufficient pressure, it may become a shale, argillite or metamorphose into slate.

The Old South Meeting House of Boston Constructed of Colonial-era Brick from Local Clay Pits
A walk on the Freedom Trail in Boston is a veritable geological field trip of the rock and stone that built the city. A good example is "Old South" built in 1729, a historic church and cherished landmark in the heart of the old city. It's the second church that occupied the site, all of which were constructed by Puritans. During the siege of Boston, British troops used the wood of the parsonage for firewood, while the church's brick construction likely saved it from a similar fate as it did during the Great Fire of 1872 that ravaged the city.

Clay's small particle size and unique crystalline structure confers it with desirable properties of plasticity (due to high water content), and brittleness, hardness and heat- and fire-resistant (upon drying and firing in a kiln at about 2,000° F). Under these conditions, clay is "metamorphosed" and undergoes a permanent physical and chemical change converting it to a ceramic material and, in the case of brick, a colorful (due to metallic oxides such as iron and magnesium), load-bearing material that is also valuable in pottery, chinas, porcelains and tiles. 

Clay is one of the oldest building materials on Earth, used by the Persians, Assyrians, Egyptians, Greeks and Romans, sun-dried in its most primitive form. The Byzantines devised a technique for exposing brick and giving it decorative expression especially when arranged in various patterns. At the beginning of the nineteenth century, mechanical brickmaking processes were employed that replaced ancient hand-fashioning methods. Between one-half and two-thirds of the world's population, in both traditional societies as well as developed countries, still live or work in buildings made with clay baked into brick.

May
The Many-Marbled Monument to George
District of Columbia


I snapped this iconic photo of the George Washington Monument from my seat on the National Mall, while waiting for my daughter’s college commencement exercises to begin. It's the world’s tallest stone structure and tallest obelisk at 554 feet and 7 11/32 inches. I couldn't help noticing that the color and texture of its stones differed markedly and wondered about its construction history. A little research confirmed that its 36,000 stones weren’t excavated from the same quarry, which explains the difference in the stones at the bottom one-third. Accounts indicate they matched initially, but differences in the composition of the carbonates have allowed weathering to accentuate the two since construction was initiated in 1848. 

Apparently, funding and concerns over the region’s swampy foundation - the original site designated by Pierre L'Enfant was moved - delayed construction for 25 years after the base had been initiated. When construction was about to resume in 1876, the builders discovered that the foundations were inadequate and the monument was sinking and tilting. To stabilize and straighten the monument, wider sub-foundations were constructed to a depth of nearly 37 feet. When construction resumed, a different marble was used. Actually, a third type of marble was used in the transition zone.

First Phase of Construction
The Washington Monument was the tallest building in the world upon its completion in 1884. The structure was completed in two phases, one private (1848-1854) and one public (1876-1884).

The first stone consists of Cockeysville Marble from quarries in the Piedmont province at Cockeysville and Texas, Maryland, just north of Baltimore. It’s a fine-grained, magnesium-rich, clear white stone with a few pale streaks or bands, which give an effect of pale gray. The marble from the Texas quarry is whiter and coarser grained and is nearly pure calcium carbonate. Some specimens of both marbles contain veins and pockets of mica and pyrite, which have stained the marble from exposure to the elements. 

In 1879 work began again on the upward projection of the monument, and four courses or rows of white marble from Sheffield, Massachusetts, were laid above the Texas marble. However, because of difficulties with timely delivery and quality control, the contract with the Sheffield quarry was annulled in 1880. The upper part of the monument was finished with Cockeysville marble.

October
Finding "Needle Ice" on Little Haystack
Franconia Ridge of the White Mountains of New Hampshire



While ascending Little Haystack Mountain on the Franconia Ridge Trail in the western White Mountains of New Hampshire, my son and I came upon a large area of “needle ice” on the trail at about 3,000 feet of elevation early in the morning. It was late October, and the night had brought temperatures below freezing but without any precipitation. It was the first time I experienced such a variant of frozen, ribbon-like water and was fascinated how it forms.


Franconia Notch State Park of the Western White Mountains of New Hampshire
Located in the heart of the White Mountains National Forest, the notch - a New England geological term for a glacially-scoured mountain pass - is a product of the last advance and retreat of the Laurentide continental ice sheet. Eight miles of north-south Interstate 93 slices through it with spectacular cliffs of Cannon Mountain on the west (former site of the "Great Stone Face" of the Old Man of the Mountain) and peaks of Franconia Ridge (Mounts Lafayette, Lincoln and Little Haystack) on the east. The ridge is notorious for its unpredictably inclement and dangerous weather at any time of the year. Its also famous for classic glacial geomorphology. Louis Agassiz, the renowned Swiss naturalist, geologist and Harvard professor, confirmed in 1847 that continental-scale glaciers were responsible for the appearance of the landscape. In fact, the terrain north of the gap (seen above) contains Alpine-like "ancient moraines" that he studied.
Aerial photo courtesy of Bill Hemmel. Please visit him at AerialPhotoNH here.

Appearing as thin, curved, filamentous and striated combs, the needle ice grows from moist, water-penetrable soil generally before melting in the warmth of the sun. Unlike frost or rime, which obtains moisture from the air, the water source for needle ice is contained within the soil. When the air temperature drops well below freezing, water in the soil may become “super-cooled” well below freezing. The cold water is drawn upward through the soil via capillary action and is rapidly frozen into ice crystals near the surface, while being “fed” as additional water seeps out from the soil and freezes. While “growing”, needle ice may lift small soil particles. Along with cyclical freezing and thawing, frozen water in its many forms contributes to soil creep and even the erosion of mountains.


My son Will and I on Little Haystack
The Franconia Ridge Traverse and the nine-mile, seven-hour Loop are one of the most popular climbs in New England. It's a small segment of the 2,180 mile-long Appalachain Trail that stretches from Georgia to northern Maine. National Geographic promoted the traverse in an article entitled "World's Best Hikes: Twenty Dream Trails", and it's just over a two hour drive from Boston! You remain above treeline for each peak on this second highest range in the White Mountains. But beware, since the weather can change on a dime. On this beautiful day, the wind was intermittently gusting upslope at 40 to 50 mph! The fascinating geology on this part of the Whites, a Jurassic ring-dike, will be the subject of a future post.


December 
Persistent "Fairy Rings" of Late Summer
Rocky Hill, Connecticut


Having just completed a late summer post on fungi (here), I was quite surprised to discover a cluster of fairy rings on a suburban Connecticut lawn and in mid-December, well after the region's first frost. Their annually, concentrically-enlargening growth is the result of successive generations of some 60 mushrooms of Basidiomycetes fungi that germinate as mushrooms when conditions are right.

Fungi, being saprotrophic, feed on decaying organic matter such as typically found in forests (called "tethered" and are related to mycorrhizal symbiotic associations with trees) and lawns (referred to as "free", since they are not associated with other organisms). The fairy ring is detectable by a circle of mushrooms as well as a necrotic zone of dead grass or, counterintuitively, a ring of thriving, dark green grass, as seen above. In the latter circumstance, the below-ground mycelium, which is somewhat analogous to the roots of vascular plants, absorbs nutrients via the secretion of enzymes from the tips of hyphae, the thread-like, microscopic filaments that comprise the mycelium.

The mycelium gradually moves radially from the center of the expanding ring, when nutrients (generally nitrogen and iron) become sufficiently depleted. When the center dies, the ring become obvious outside the necrotic zone. Surprisingly, some fungi produce chemicals called gibberellins that act like hormones, which favorably affect plants causing rapid luxuriant growth.


Modified from victoriaweb.com 

Fairy rings are the subject of folklore, myth and the supernatural, especially in Western Europe. In France, they are referred to as “sorcerers’ rings” and in Germany “witches’ rings.” Some believe that anyone stepping into an empty fairy ring will die young. Those that violate the perimeter become invisible to those outside and may be unable leave the circle. The fairies force intruders to dance till exhausted, dead, or in the throes of madness. One of the largest fairy rings ever found is near the city of Belfort in northeastern France. It measures some 2,000 feet in diameter and, based on the rate of growth and expansion, is estimated to be 700 years old.


December
Cenozoic Sunrise over a Widening Atlantic Ocean
In another place. In another time. 


Thanks for following my blog, and have a Happy and Healthy New Year!

Sunday, November 6, 2016

Neighborhood Mushroom Watch (Someone’s Got To Do It): Part III – Spore Release and Dispersal

“For the rain had ceased at last, and a sickly autumn sun shone upon a land,
which was soaked and sodden with water. Wet and rotten leaves 
reeked and festered under the foul haze which rose from the woods. 
The fields were spotted with monstrous fungi of a size and color
never matched before - scarlet and mauve and liver and black. 
It was as though the sick earth had burst into foul pustules; 
mildew and lichen mottled the walls, and with that filthy crop 
Death sprang also from the water-soaked earth.”

From Sir Nigel by Sir Arthur Conon Doyle, creator of Sherlock Holmes

The summer of 2016 in southern New England was mired in the most severe drought in nearly a decade. While everyone reveled in the near "perfect" weather, wells began to dry up, lakes became historically low and waterways withered into ponds and long stretches of exposed beds. Watering restrictions and bans were issued as some towns purchased water from the state's back-up reservoirs. Farmers lost millions in production, and officials declared many regions a natural disaster area.

Welcomed rains triumphantly arrived in late August, but it was too little, too late for stunted crops - but not so for fungi. As if waiting for the appropriate conditions, they responded with astounding speed to the call of wet weather by fruiting on forest floors, suburban lawns, tree bark, rotting stumps, decomposing leaves, wood mulch, compost and manure. The myco-celebration was brief, but it generated and released countless gazillions of spores throughout the night and before dawn. It's fungi's sole mission - species perpetuation assisted by gravity, wind, water, insects, mammals and ejection ballisitics.


With a Foul Stench, the Erotic and Vile, Rude and Provocative,
Shameless Mutinus Elegans Demands Your Fervant Attention

This is my third post on the fungi of New England in which I investigate various modes and mechanisms of spore release and dispersal. Part I (here) discusses fungal basics and their otherworldly lifestyles, while on a quest to study local members of Kingdom Fungi. Part II (here) is a "Summer Sampler" of some remarkable specimens that fruited overnight in my neighborhood.

MUTINUS ELEGANS - PUTRID GOO ENTICES AGENTS OF DISPERSAL
Emerging mysteriously overnight after three days of soaking rain, over two dozen M. elegans magically sprang up in gregarious clusters from a bed of decomposing wood mulch and leaf litter in my yard. Its genus name, Mutinus, refers to the Roman phallic deity, and its order name is Phallales, as one might expect. For obvious reasons, it’s commonly called the Dog Stinkhorn, Headless Stinkhorn and the Devil's Dipstick. A related and frequently mistaken species, Mutinus caninus, is more reddish in color and smaller. 

They're both edible but hardly tempting, although they've been used in potions and ointments for gout, epilepsy and gangrenous ulcers and fed to cattle in parts of Europe as aphrodisiacs (no surprise). Not uncommon among fungi (Penecillium is the best example), the stinkhorn possesses antibiotic (anitbacterial and antifungal) properties.


And plants at whose name the verse feels loath,
Filled the place with a monstrous undergrowth.
Prickly, and pulpous, and blistering, and blue,
Livid and starred with a lurid dew.

From "The Sensitive Plant" by Percy Bysshe Shelley, 1820.
The poet is "loathe" to include the name stinkhorn in verse.

The somatic phase of growth begins with the stalk's (stipe) emergence from a partially-submerged, creamy-white, two to three centimeter, egg-shaped volva that is attached to the soil by a thick mycelial cord. Within hours, the capless mushroom acquired almost five centimeters of height. The jaw-dropping spectacle is accomplished so quickly since the stinkhorn is fully-formed in a compressed state within the "egg" - its appearance related more to expansion than cellular growth. The stinkhorn's slightly curved and erect body is hollow internally with an orange peel-like, spongy external surface that is punctuated with minute interconnecting chambers. 




  
During the reproductive phase of growth, which quickly follows, the apex of the stalk becomes smeared with an olive-brown, fecal-smelling, mucilaginous slime (gleba). The malodorous goo is enriched with spores produced within the volva and passively exudes from a small opening at the tip during its erection. The lively color of the stinkhorn is visually enticing to insects as is the gleba, which is an offensive olfactory mix of skunk-smelling methylmercaptan and rotten egg-infamous hydrogen sulfide. The gelatinous mass of spores irresistibly attracts mycophagous (fungi-eating) insects such as the metallic-colored Bluebottle fly that traipse through and ingest it.





Rather than relying on wind and gravity to disperse the spores, the two commonest dispersal modalities for all fungal spores, the appendages and bodies of insects serve as vectors of dissemination. Called entomophilus dispersal, the cache of spores are unknowingly removed during its grooming elsewhere. Spore ingestion may also contribute to dispersal, since they're acid resistant and can germinate elsewhere following defecation.

In a day or two with its reproductive obligation fulfilled, the fruiting body has begun to wither, becoming limp and flaccid with little remaining gleba, yet a lone fly is still attracted by the fetid scent. Off to the left, also promoted to germinate by the wet weather, a bevy of tiny cup-shaped Bird's Nest fungi are awaiting the next rain to facilitate spore release via a uniquely different mode and dispersal mechanism.






CYATHUS STRIATUS - SPLASH-CUP RELEASE MECHANISM
Sprinkled around the stinkhorns and easy-to-miss by virtue of their tiny 3/8th inch-diameter, Bird's Nest fungi easily can catch the eye by their grouping into tight clusters on rotting wood mulch. Its fluted fruiting body resembles a miniature bird's nest replete with eggs, which are lens-shaped periodoles - packets of millions of spores and the specialized cells that form them. The "nest" (peridium) is a cup-shaped structure that quickly loses its membranous, lid-like cover structure (epiphragm) upon germination. 



Cyathus Striatus - A Master at Spore Dispersal
Initially, Bird's Nest fungi have immature fruiting bodies that are spheroidal with a hairy projections on the exterior and contain lens-shaped periodoles that contain spores. a striated interior.  When mature, the mushrooms rupture exposing the striated namesake-interior and appear like tiny eggs with spores enclosed within the protective sac of the periodole "eggs." They fruited in concert with the stinkhorns and like them, are saprophytic - enzymatically feeding on decomposing organic remains.

As do plants, fungi utilize two modes to extend their range: growth into a neighboring area, which is a slow process (fairy rings are an example) or the dispersal of spores utilizing various vectors. Compared to seeds, spores are microscopic (~2-5 μm), lighter, less dense and more aerodynamically-designed and can travel considerable distances via the wind - the dispersal vector to which most spores subscribe. 


The Mushroom is the Elf of Plants-
At Evening, it is not-
At Morning, in a Truffled Hut
It stop upon a Spot

From "The Mushroom is the Elf of Plants" by Emily Dickinson

A region of micro-still air surrounds the spore-producing gills of mushrooms, which spores that rely on the wind for dispersal must first clear. In addition, most fungi are below the thin, non-turbulent "boundary layer" of air at ground level. When air flows over a surface, such as the ground, friction reduces current flow and creates a transition zone of calm air between the two stable systems. In order to become airborne, many fungi have developed highly creative mechanisms for assisting spores to penetrate through the layer in order to utilize the wind for dispersal.



A Cluster of Bird's Nest Peridia Filled with Lens-Shaped Periodoles Awaiting the Next Rain
The Bird's Nest mature fruitbodies are cone-shaped and covered externally with shaggy, dark brown hairs, whereas, the inside wall is smooth, striated and gray and filled with lens-shaped periodoles. The fungus typically fruits on beds of decomposing woody mulch.

C. striatus has adapted to the problem of both discharge and dispersal beyond the boundary layer via ballistospory, by literally catapulting spores into the air. The Bird's Nest's "splash-cup" mechanism is accomplished when one-eighth inch raindrops travelling at 13 to 26 fps strike the cup and eject periodoles a foot or two from the "nest." Each periodole is attached to the cup's inner wall by a cord-like funiculus, which tears from the cup and serves as an attachment mechanism by entangling a sticky holdfast called a hapteron to a nearby plant. Once above the boundary layer, wind currents disseminate the spores. Voila!


The Innovative "Splash-Cup" Mechanism for Releasing and Dispersing Spores
 (A), Forceful raindrops strike the peridium; (B), Periodoles are ballistically ejected through the boundary layer; (C), The holdfast attachment snares onto anything in its trajectory; (D), Spore release and dispersion follows. 

Modified Images and Courtesy of Nicholas Money, Professor of Botany, Miami University.

FUNGI AT THE MICROSCOPIC LEVEL
Both M. elegans and C. striatus are members of phylum Basidiomycota. Along with larger, sister-phylum Ascomycota ("sac fungi"), they are members of the "higher fungi" sub-kingdom Dikarya, which is contained within Kingdom Fungi. Basidiomycetes (a non-taxonomic, obsolete class but convenient and informal term) produce most of the large fruiting bodies found in nature - the specialized reproductive structures that house basidia such as mushrooms, puffballs, bracket fungi, yeasts and so on. 

Its members largely reproduce sexually via specialized cavate (club-shaped), microscopic spore-producing and spore-bearing cells called basidia that typically blanket the gills located outside the fruiting body such as found on the underside of mushrooms. In the case of the Dog stinkhorn's volva and Bird's Nest's periodoles, spores mature inside the fruiting body instead of discharging them directly into the air. The internal production of spores accounts for the number of creative ways they are released in order to "get them outside." The gasteroid fungi were originally classified as gasteromycetes or "stomach fungi", another obsolete term of reference since many members are unrelated.


Cross-section of a Mushroom
Modified from nomadsonwheels.com 

Fungi are constructed of a thread-like network of mycelia (pl.). It's the whitish, fuzzy cobweb-like growth found on the forest floor beneath an overturned log. The mycelium permeates throughout the body of the fungus. On a microscopic level, it's comprised of an interconnecting and branching mass of tubular cells called hyphae (2-10 μm in diameter) that are responsible for the growth of the fungus and its nutrition. The hyphae and mycelium channel nutrients to form fast-growing fruiting bodies. 


SEM of Fungal Mycelium and Basidia with Spores
(Left), Mycelial mass of interconnecting and branching hyphae. It's role is to penetrate
(Right), Scanning Electron Micrograph of basidia and associated basidiospores. Basidiospores have a single haploid nucleus. 


COMING TO TERMS
Mutinus elegans typically appears on decomposing woody substrates, which makes it saprobicobtaining nutrition from a dead or dying host. In contrast, plants are autotrophic, capable of providing and creating their own "food" (glucose) by converting carbon dioxide and water in the presence of sunlight (photosynthesis). Fungi and animals are heterotrophs, obtaining nutrition from their surroundings by secreting enzymes that break down (decompose) complex molecules into smaller, more absorbable compounds. Fungi digest foods externally via "chemoheterotrophic extracellular digestion" and then absorb it versus animals that ingest foods and digest it internally. Fungi are often parasiticderiving nutrition from an unhealthy substrate such as a tree, and can continue as saprobic, after the host succumbs (or contribute to its demise). 

Along with soil bacteria, fungi are the great decomposers and recyclers of our terrestrial ecosystem. The disassembling of large organic molecules into simpler forms is a vital process that nourishes other life forms by re-entering the food chain. Without rot and decay there would be no life.

Fungi's Essential Role in the Ecosystem
The complex organic molecules of detritus (dead plant material, animal remains and fecal material) are broken down by decomposers such as fungi, bacteria and earthworms into inorganic derivatives such as carbon dioxide, water and minerals (such as nitrogen and phosphorus). Fungi decompose organic matter by releasing enzymes, after which they absorb nutrients made available within the decaying material while returning (recycling) carbon and nutrients to the ecosystem for other living organisms such as vascular plants for growth and replenishing carbon dioxide to the atmosphere.
Modified from biotrick.com

IN A KINGDOM OF THEIR OWN
The study and classification of fungi - mycology - was initially a naked-eye endeavor based on morphology and reproductive structures. It was originally a branch of botany, although fungi were always recognized as different from plants. The science became more exacting with the invention of the light microscope in the 16th century and far more precise with the advent of SEM (Scanning Electron Microscopy) and molecular genetics in the 20th century. It led to the placement of all fungi within Kingdom Fungi of which taxonomists have classified perhaps 140,000 types, but the numbers suggest that only 10% are known.

Fungi were originally included within Kingdom Plantae based on anatomical and lifestyle similarities such as vegetative growth (the period between germination and reproductive stages), nonmotility (rendered via firm attachment to a substrate), rigidity (although fungal cell walls contain the rigidity-conferring, carbohydrate-polymer chitin occurring in arthropod exoskeletons, whereas plant cell walls are made of cellulose and animals lack a cell wall) and seed-like spores (superficially similar to plant seeds but fungal spores are immensely different and of course animal seeds are gametes and totally different). Remember that superficial resemblances are not a reflection of phylogeny, only convergent evolution


Many Aspects of Fungal Growth are Plant-like
The striated and gilled mushrooms of Mycena leaiana are visible with the naked eye, and are thus classified as macrofungi, which are largely found in subdivisions Basidiomycota and Ascomycota, although many are capless. Growing laterally from the forest floor in clusters, Mycena, like many mushrooms, orient themselves via negative gravitropism (plants orient to the sun called phototropism), so that the spores fall directly downward but above the boundary layer. It also protects the developing spores from rain. Fungi are also capable of plagiotropism, in which the apical portion of the stem bends upward towards vertical and not just at the base.

Unlike plants, fungi lack true roots, stems and leaves, lack vascular tissue as do plants, and don't possess chlorophyll, and therefore can’t manufacture food via photosynthesis as do plants. And unlike seeds, spores are microscopic, unicellular, produced in far greater numbers and don't contain miniature plant embryos and food stores. Seeds and spores share haploidy and diploidy conditions (half and normal chromosomal numbers), but there are major differences regarding the ultimate goals of sporogenesis - mass production of spores versus fewer spores but with genetic variability (explained in post Part I here).

Fungi and the Phylogenetic Tree of Life
The three-domain system of life (Carl Woese, 1990), which uses ribosomal RNA protein sequences, adds a level of classification "above" kingdoms and divides life forms into Bacteria, Archaea and Eukarya. All life is theorized to have evolved from a "universal common ancestor." First classified as plants, fungi (red arrow) are thought to have diverged from plants and animals but are more closely related to the latter. Fungus-like slime and water molds, although structurally similar to fungi, belong to Kingdom Protista (Protoctista). Unlike single-celled bacteria and archaea that are prokaryotic (lack membrane-bound cellular organelles) and are classified within separate domains, fungi, like plants and animals, are eukaryotic (contain membrane-bound organelles, especially a nucleus).
Modified from Biology of Plants, Seventh Edition, W.H. Freeman and Company, 2005

WHO'S RELATED TO WHOM?
Most of the scientific community believes that dinosaurs and birds are phylogenetically related, as are mammals and reptiles, apes and humans, and so on. They all belong to Kingdom Animalia and, along with plants, are eukaryotes (organisms with cells that contain membrane-bound organelles, especially a nucleus). So, how are plants, animals and fungi related being in separate kingdoms? Is there a common ancestor?

Although relationships are unresolved, molecular analyses suggest a three-way split between between fungi, plants and animals estimated at 1,576 +/- 88 Ma and that fungi and animals were derived from a common ancestor that existed ~1 billion years ago. Subsequent to that, terrestrial colonization of land by fungi remains somewhat speculative and obscure (see Prototaxites below). No ancient fossils exist, since fungi don't biomineralize (produce preservable minerals within biological tissues). 

Plants and fungi exist in symbiotic relationships that are thought to have developed long ago. Co-operative interactions with fungi may have helped early plants adapt to the stresses of the terrestrial realm. Thus, it's likely that fungi were on land with plants in the Devonian, although molecular clock estimates indicate fungi gained ground earlier in the Cambrian. 

Fungal Columns of Prototaxites Dominate a Speculative Landscape
Although alternative older views suggest it was a large vascular plant, it is currently thought that, in the Late Silurian to the Late Devonian, Prototaxites formed large trunk-like structures up to 1 meter wide and 26 feet high, the largest organism of the period. It possessed a tubular structure identified in fossils most like fungi of phylum Glomeromycota and must have had an extensive mycelium to have obtained sufficient organic carbon to accumulate the necessary biomass for the giant fungus.
Used with permission from scientist F. Hueber (who redescribed Prototaxites as a fungus in 2001 after 20 years of research). Painting by M. Parrish with permission and courtesy of the Smithsonian Institution.

OMPHALOTUS ILLUDENS - BULLER DROP BALLISTOSPORY
Commonly referred to as the Jack-O-Lantern mushroom, for obvious reasons, and the fact that it fruits in the fall, Omphalotus illudens is saprobic, in this case deriving nourishment from the roots of an unhealthy acacia tree. It's typically found in large clumps on decaying wood, buried roots or at the base of hardwood trees in eastern North America. Its agaric (mushroom-shaped fruiting body) is bright-orange with decurrent (descending on the stalk) gills (thin plates beneath the mushroom cap that contain spore-producing basidia). Don't be enticed by the seductive, culinary beauty of the mushrooms. They are extremely poisonous when ingested!

Omphalotus spores are gravity-released from the undersurface of the fruiting body, which allows wind currents to disperse them called anemophilous dispersal. The large number of mushrooms in clusters (many of which reach six inches in width) and the massive numbers of spores that are generated (a large mushroom can shed 40 million spores per hour) better the odds that at least a few spores will germinate somewhere downwind if the conditions are right. How do the spores get off the gills and away from the mushroom cap?






All members of phylum Basidiomycota, such as the Dog Stinkhorn, Bird's Nest and Jack O'Lantern fungi, possess spore-producing basidia cells. As mentioned, they line the gills on the undersurface of mushrooms or equivalent reproductive structures. Each spore secretes a small amount of sugar that absorbs moisture from the humid air around the gills, which condenses on the spore's surface in a thin film. Condensed water also forms a tiny Buller's drop at the base of the spore at the sterigma, a tiny extension of each basidium (sing.) As the drop gradually increases in size, it suddenly contacts the film and quickly collapses as it "feeds" additional moisture to the spore's surface. 

The micro-event shifts enormous mass to the spore providing sufficient momentum to accelerate the "ballistospore" 25,000 times the force of gravity and discharge it through the micro-thin boundary layer of air around the gills to the wind. By comparison, the NASA Space Shuttle possesses a maximum acceleration of only a few times the force of gravity. The mechanism of ballistospory is utilized in many unrelated mushroom groups and is the result of parallel co-evolution.


(Top), Time-Lapse Photos of Micromechanical Forcible Discharge of a Spore Using a Buller's Drop
The transfer of energy from the drop to the spore releases the spore from its supporting structure. During the early phase of coelscence process, the sterigma provides the external force that prevents the spore from moving toward the drop. In the late phase of the coalescence process, the sterigma is now put under tension and should fracture easily to prevent dissipation of the spore energy. The kinetic energy of the spore after ejection ejects it through the boundary layer. 
From Xavier Noblin et al, 2009.
(Bottom), High-Speed Video Imaging Demonstrating Ballistospore Discharge
From YouTube



There is no known analog in nature of this unique, musculature-less, micro-mechanical process in animals, plants or bacteria. The production of many trillions of spores ensures that some will survive once dispersed by the wind. Some basidiomycetes lack forcible discharge such as the stinkhorns that use insect vectors, which is considered an evolutionary loss ancestral to all basidiomycetes.

PARASOLA PLICATILIS - AUTOLYSIS OF THE FRUITING BODY
Subsequent to genetic investigation, many coprinoid fungi - all members of Basidimycota - have been reclassified, many with a name change. In fact, binomial scientific names of all fungi often change with the advent of more refined genetic analyses. This is true especially of "gill" fungi. 

With Parasola plicatilis, the group acquired the coprinus genus name, because they frequently "live on dung", while plicatilis in Latin means "folded" or "wrinkled". Although this sole, delicate beauty fruited one morning on wood chips, they are also purported to live in grassy areas and forest litter. With a delicate, long stalk, cover of tiny hairs and a gracefully unfurled parasol, P. plicatilis doesn't remain too long in the heat of the day. There's a reason, and it's related to spore release and dispersal. 





As the mushroom matures, the stem begins to rapidly elongate followed by liquefaction of the cap and gills within hours via the mushroom's autolytic enzymes. "Self-digestion" allows the mushroom's black spores to release to the wind, facilitated by the elongate stalk well above the boundary layer. The blackish goo that forms following lysis provides the group's more common name "inky caps", which actually can be used for writing. 

GANODERMA AUSTRALE - GRAVITY DOES ITS THING
This common perennial, semicircular-shaped, large fungus protrudes in a shelf-like manner from its host, a rotting stump. G. australe's spores are produced inside tiny, rigid tubes rather than gills that line the underside of the fruitbody. They open to the exterior and lend a perforated appearance to the fungus, hence the species common name polypore and bracket fungus due to its shelf-like growth on the sides of trees and stumps. Unlike mushrooms that morph into a putrefying mass in days following the reproductive phase, bracket fungi can last months, through winter and some years owing to their woody consistency.


Various Spore-bearing Surfaces Under Caps
Modified from maturehealth.files.wordpress.com

It's parasitic in early stages (fungal tree pathogens produce biodelignification or white heart rot in oak, birch, beech, chestnut and a few others) and becomes saprobic as the host dies (which can have enormous economic and environmental impact). They're commonly called "conks", because the fungal "wood" is corky in texture with a tough, leathery and shiny surface (ganoderma means "shining skin"). Not surprisingly, they're inedible, although some members of the genus have been used to make tea and for medicinal purposes in China and Japan for thousands of years. 

With a drab, brownish uppersurface, the brilliant white, rounded collar and undersurface are an indication that brown spores are ready to be released by basida that line the tubuli. Succumbing to gravity, they have colored the fruiting body, adjacent bark and underlying soil with a fine, brown dust upon their release. You can even ascertain the direction of the prevailing wind to the east from the color of the adjacent bark.



The Shelf or Bracket Fungus Ganoderma Australe
Growing on trees that are naturally elevated from the ground, a stalk is unnecessary to elevate the fruiting body above the boundary layer's still air. Success of germination is ensured by the enormous number of spores that are generated over the many years that the fungus can live, which often can be calculated by counting the growth zones or furrows on the cap as the cap extends outward and downward. 


SCLERODERMA CITRINUM - WINNING BY THE NUMBERS
In contrast to mushrooms and like the aforementioned stinkhorns and bird's nest fungi, S. citrinum produces spores inside the fruit body. It's often confused with puffballs, which are soft and spongy when ripe, Scleroderma ("hard skin") citrinum is an earthball fungus. Superficially, the two are similar but are unrelated. Also known as Common Earthball or Pigskin Poison Puffball, it's typically found found solitary or in groups in the woods on rotten wood and leafy, twiggy ground. 

Because they are often partially buried, they have been mistaken as truffles, a non-farmable ascomycete fungus that is highly prized for its culinary attributes. That would an unfortunate mistake for the forager, since earthballs have an unpleasant flavor and are mildly poisonous causing GI disturbances, chills and sweats. It would be financially beneficial to recognize the difference in the field, since this year a 4.16 pound white truffle sold at a Sotheby's auction for $61,250. And yet, it was a bargain, since abundant rainfall in Italy has produced a bumper crop that brought prices down.





S. citrinum is yellow-brown in color and covered with a scaly raised and ornamental mosaic of attractive brownish geometrics on its tough, rind-like peridium (skin). It typically has an ellipsoid or globose (round) to pear-shaped fruit body that contains trillions of spores that develop within locules (small cavities or glebal chambers). Unlike puffballs that are saprotrophs, earthballs are mycorrhizal ("fungus-root"), entering into a symbiotic relationship with vascular plants. 

In fact, over 90 percent of all plant families are known to partner with mycorrhizal fungi. By doing so, the fungus provides increased water and nutrient absorption while deriving carbohydrates formed from photosynthesis. It often explains why crops fail and why a newly planted sapling doesn't "take." Gardeners recognize this from their active use of compost.
  
Typical Fine-Branching Mycorhizzal NetworkContrary to one's common perception, the white fungal network of hyphael cells in intimate contact (ectomycorhizzal, outside of root cells and penetrating within, endomycorrhizal) with the roots of vascular plants and trees is responsible for the uptake of nutrients, not the plant roots.
From motherearthnews.com and illustrated by Michael Rothman

S. citrinum's is a member of Basidiomycota, but unlike mushrooms it's spore-producing basidia cells line and mature within the puffball's enclosed, globular interior. It's 
considered to be a gasteroid ("stomach") fungus for obvious reasons. Puffballs, when provoked by rain, implode and release trillions of spores to the wind in a powdery, smoke-like puff through a small aperture on the the superior surface of the fruiting body. On the other hand, earthballs, which also rely on a massive release of spores, develop fissures when ripe in order to release their bounty.

PUNCTELIA APPALACHENSIS - GONE WITH THE WIND
Instead of parasitizing or scavenging other organisms, some 13,500 fungi to date have discovered farming by being intimately involved in a symbiotic relationship. It's a mutualistic and intimate partnership with dissimilar organism(s). The affiliation allows the lichen to endure extremes of temperature, nutrient availability, solar radiation and aridity, seemingly everything adversely environmental with the exception air pollution. As a result, lichens are typically not found in big cities ("lichen deserts") and industrial regions due to high levels of sulfur dioxide.

There is a low mist in the woods—
It is a good day to study lichens.

From A Year in Thoreau's Journal by Henry David Thoreau, 1851.

The interdependent partnership is between a mycobiont, a lichenized fungus (the major partner and usually a member of Ascomycota), and a photobiont, a green alga or cyanobacteria (formerly called blue-green algae) or both. The mycobiont derives organic molecules (generally simple carbohydrates such as glucose) from photosynthesis carried out by the photobiont, while the alga is protected against desiccation and excessive solar radiation, and receives mineral nutrition from the mycobiont's atmospheric and substrate surfaces. Cyanobacterial partners provide nitrogen to its fungal partner.


Schematic Cross-Section of a Typical Foliose Lichen
Arranged in a layered sheet-like manner, a foliose lichen's thallus consists of: 1.) A colorful upper cortex of interwoven, highly-compacted, physically-protective ultraviolet light-filtering pigment of fungal hyphae); 2.) A green or blue-green algal photosynthesizing photobiont surrounded by the strands of the mycobiont; 3.) A spongy, middle medulla of loosely-packed, thread-like hyphae; 4.) A lower cortex of; 5.) Anchoring hyphae on the substrate (rhizines) without vascular capabilities like plants. The thallus of a lichen is the vegetative, non-reproductive "body" of the lichen. Other lichens possess a somewhat different morphology such as a missing lower cortex.
Modified from Wikipedia, artist JDurant and www.autocww2.colorado.edu/~toldy2/E64ContentFiles/AlgaeAndFungi/Lichen.html

Very common in deciduous woods and forests of New England, foliose Punctelia appalachensis is accompanied by various tiny crustose lichens was growing on a rotting log in my back lot (below). The lichen has a greenish, mineral-gray thallus (vegetative body) with divided lobes and non-ciliated ("hairy") margins. Notice the green photosynthetically-active center section. That classifies it as a chlorolichen, whereas a lichen with a cyanobacterial partner is a cyanolichen



A Large Foliose Lichen Shares a Decomposing Log with Numerous Diminutive Squamulose Forms
This Punctelia appalachensis is covered with spores. Lichens are found in many growth forms: foliose (leaf-like lobes that are easily removed from the substrate), fruticose (shrubby or pendant), crustose (most common, crust- or coral-like and firmly-anchored by root-like rhizines), leprose (powdery) and squamulose (scale-like lobes).

Lichen reproduction is not a straightforward event, since lichens consist of two or even three distinct organisms that each participate in the process. Lichens reproduce asexually utilizing openings on the thallus called soralia that contain dust-like granular particles (soredia) and that contain fungal and algal cells from the parent lichen and grow into a new thallus. Alternately, tiny, cylindrical projections (isidia) on the surface that incorporate both mycobiont and photobiont can easily break off (fragmentation) and grow elsewhere on a suitable substrate.

Sexual reproduction occurs when lichens produce miniature-appearing, cup-shaped fungal fruiting bodies (apothecia) that contain spores and require the appropriate photosynthetic partner to lichenize. Our Punctelia specimen, being a member of Ascomycota (the other higher "true fungus" along with Basidiomycota and the most common mycobiont), asexually produces ascospores that take to the wind for dispersal. 



By the way, symbiosis exists between many other life forms. Jellyfish contain an alga (zooxanthellae) within their tissues as do reef-building coral, neither of which can survive on their own. It explains why jellyfish frequently swim inverted or dwell in shallow sunlit waters within the photic zone. Lichen's fungal members can't live and grow without their communal partner and are never found in nature without it, whereas, the photobionts, whether algal or cyanobacterial, can survive independently in nature. 

A DEDICATION
This post is dedicated to botanist, geologist, naturalist and fellow blogger Hollis Marriott, who always seems to like it when I post on something that grows. Please visit her blog par excellence "In the Company of Plants and Rocks" (here).

VERY INFORMATIVE RESOURCES IN PRINT
• Kingdom Fungi by Steven L. Stephenson 
• Macrolichens of New England by James W. and Patricia L. Hinds
• Mushroom by Nicholas P. Money 
• Mushrooms Demystified by David Arora
• Mushrooms of Northeast North America by George Barron 
• Mushrooms, Simon and Schuster’s Guide by Gary H. Lincoff

A FEW OF THE MANY EXCELLENT PAPERS ON-LINE
•  A Higher-Level Phylogenetic Classification of the Fungi by David S. Hibbett et al, Mycological Research III, 2007 (here).
•  Field Guide to Common Macrofungi in Eastern Forests and Their Ecosystem Functions by Michael E. Ostry et al, U.S. Forest Service, 2010 (here).
•  Mycelium Running by Paul Stamets, Ten Speed Press, 2005 (here).
•  Towards a Natural System of Organisms: Proposal for the Domains Archaea, Bacteria, and Eucarya by C.R. Woese et al, Proc. Natl. Aca. Sci., June 1990 (here).
•  Weathering of Rocks Induced by Lichen Colonization — A Review by Jie Chen et al, Elsevier, Catena 39,2000 (here).
•  Surface Tension Propulsion of Fungal Spores by Xavier Noblin et al, The Journal of Experimental Biology 212, 2009 (here).