Fairy Rings

A perfect circle of mushrooms.  They pop up after a rain in summer or fall.  A fairy ring.  The name suggests magic and there is a deal of biological magic taking place.  There are several fairy rings in our suburban neighborhood in North Carolina.  The one we see the most is a ring of the poisonous mushroom Chlorophyllum molybdites. This fairy ring starts with a single, microscopic spore of the fungus landing in the soil.  This spore germinates and sends out hyphae, microscopic threads of cells, that absorb nutrients from the soil.  The hyphae grow out symmetrically in all directions making a circular colony fungus. As the colony gets larger the older part in the center dies and the living portion is along the perimeter of the colony.  When the moisture and temperature conditions are right, the hyphae on the circumference send up mushrooms in a ring.  The mushrooms carry out sexual reproduction and release more spores.  These spores float through the air and if they land on a favorable patch of ground, a new fungal colony can form.    

A fairy ring of Chlorophyllum molybdites on a lawn in Salisbury, NC. 

Chlorophyllum molybdites makes a large white mushroom.  The stalk of the mushroom has a distinctive ring just below the cap.  The mushroom’s cap has off-white scales on the top and spore producing gills on the bottom.  One of the unique features of Chlorophyllum molybdites is it makes green spores.  The spores give the gills a pale green color too.  Spore prints are a good way to see the color of fungal spores.  To make a spore print you remove the stalk from the mushroom, lay it on a piece of paper, cover it with a bowl and wait 24 hours.  The spores are released and fall straight down onto the paper making an exact print of the gills and showing the color of the spores too. 

A single mushroom of Chlorophyllum molybdites just emerged from a lawn.

Two Chlorophyllum molybdites mushrooms with scales on the cap. 

The underside of the cap of Chlorophyllum molybdites showing the ring on the stalk,

A closeup of the gills of Chlorophyllum molybdites with the green color.

Spore print of Chlorophyllum molybdites.  The spores make an exact impression
of the gills and show the spore color.

Chlorophyllum molybdites has several common names.  The most interesting is vomiter from the consequence of ingesting this poisonous mushroom.  Chlorophyllum molybdites causes most of the mushroom poisoning cases in the United States.  A person unlucky enough to eat Chlorophyllum molybdites experiences gastrointestinal distress.  It starts with cramps, then vomiting and diarrhea, sometimes-bloody diarrhea.   Chlorophyllum poisoning is almost never fatal and the symptoms clear up in a couple of uncomfortable days. 

Fairy ring season is upon us.  Enjoy the magic but don’t eat the mushrooms. 

Moth Mimic

You can see these moths, these hummingbird moths, all summer.  They hover, move from flower to flower and sip nectar.  They are unusual for moths because they fly during the day time.  This group of moths has a bewildering number of names: hummingbird moth, hawk moth, bumblebee moth, sphinx moth.  With a casual glance these moths can be mistaken for a hummingbird or a bee and that mistaken identity gives them a couple of their common names.  There are three species of hummingbird moths in Eastern North America.  This summer we hosted a group of Hemaris diffinis. These moths fed on beebalm, milkweed, lantana and other flowers in our yard. 

 

The hummingbird moth Hemaris diffinis feeding on Lantana camara in North Carolina

Hemaris diffinis, besides being called all these other names has yet another common name, snowberry clearwing.  Snowberry (Symphoricarpos) is a member of the honeysuckle family and Hemaris diffinis uses this plant as a host for its eggs and larvae.  The clearwing part of the name comes from the transparent areas on the moth’s wings.  Hemaris diffinis has a large body with a golden thorax and a black abdomen.  This yellow and black pattern is like that of several species of bumblebees.  At the tip of the abdomen, this hummingbird moth has a fan of bristles that resemble the tail of a hummingbird.  Hemaris diffinis does not flap as fast as a hummingbird but the clear areas of the wings make them appear to be a blur, just like the wings of a hummingbird.  Hemaris diffinis has an extendible mouthpart, called the proboscis, which it uses to sip nectar from flowers.  The proboscis even resembles the beak of a hummingbird.  

The video above shows Hermaris diffinis, with its yellow body and black abdomen, hovering as it feeds on Lantana.  This is similar to the color pattern of the Common Bumblebee Bombus impatiens in the next section of the video.  Finally a male Ruby-throated Hummingbird perched on and hovering near a hummingbird feeder shows a similar flight and feeding pattern to the moth. 

Hemaris diffinis is a mimic and it is mimicking both hummingbirds and large bees.  The question is, why?  It is easy to explain mimicking a bee.  Bees are able to sting and they advertise this fact by bold patterns and colors of yellow and black.  This yellow and black pattern is a well know warning to potential predators.  A number of insects including flies and beetles mimic bees and enjoy protection from bird predators.  But why would a moth mimic a hummingbird?   The birds that prey on moths do not hunt hummingbirds, so being mistaken for a hummingbird is a second level of protection. 

Summer is still going and the hummingbird moths are still flying.  Go out and enjoy these double mimics in fields and gardens. 

The (Metaphorical) Big Fish

This post is not really about fish but it is inspired by anglers.  Fishermen and women have stories and the best stories are about fish that got away.  As these stories are told and retold the fish get bigger, they fight harder and they leap more dramatically.  Taking photos of animals is kind of like fishing because lots of times the big ones get away.  Here are some of the ones that got away from me photographically. 

This White-tailed Deer (Odocoileus virginianus) saw me bring up the camera and it sprung away.

A Cooper's hawk (Accipiter cooperi) was perched near the Salisbury, NC Greenway.  As I tried to take a picture the hawk flew toward me with a glare in its eyes.

This large blue dragonfly, an Eastern Pondhawk (Erythemis simplicicollis) was using a twig for a perch.  This is the Eastern Pondhawk leaving the perch.

A male Ruby-throated Hummingbird (Archilochus colubris) escaped from focus at a feeder in our yard. 

A juvenile Five-lined Skink (Eumeces fasicatus)was climbing fast up the wall of our house and ran out of the frame.

This male Summer Tanager (Piranga rubra) was perched in a scrubby tree on a Piedmont Prairie in Mecklenburg County, NC.  Then it flew.

I was in a swamp in Rowan County, NC trying to get the definitive picture of a Prothonotary Warbler (Protonotaria citrea) .  This male jumped at the wrong moment.  

This Pied-billed Grebe (Podilymbus podiceps) was feeding in a pond in Palm Beach County, FL when it took a dive.

I was photographing Gray Squirrels (Sciurus carolinensis) in Spencer, NC when this one bounded away.

A Red-shouldered Hawk (Buteo lineatus) was hunting along a creek in Clayton County, GA when it decided I was too close and flew away. 

A Monarch Butterfly (Danaus plexippus) departs from a Tropical Milkweed (Ascelpias curassavica) in Salisbury, NC.

Driving through Florida's Merritt Island National Wildlife Refuge on a September afternoon, Diane and I could not believe our luck.  Two Peregrine Falcons (Falco peregrinus) were roosting in the same dead pine.  When we got close enough to take a picture, a Turkey Vulture (Cathartes aura) decided to land in the same tree.  You can see one Peregrine still at the top of the tree and the other Peregrine, which was displaced by the Vulture is just coming out from behind the tree on the left.  The Vulture is landing in the middle. 

We took a boat this summer in Alaska and the captain had posted a sign that said, "There are no bad birds".  I try to say, "There are no bad pictures", but I am not so sure.

A Blue Green Snake

Rough green snakes, Opheodrys aestivus, are common in the southeast.  These small snakes are bright green on their backs and sides with a yellowish-white belly.  They are among the most arboreal of the snakes in this region, climbing through the branches of trees and shrubs where they hunt insects and other invertebrates.  The largest rough green snake might be two feet in length.  They are called rough because their scales have a ridge running down the middle (the keel) that gives them a rough feel when handled.  These snakes are good-natured and don’t bite if you pick them up to see how rough they are. 

Rough green snake (Opheodrys aestivus) showing its bright green color

Diane and I regularly see rough green snakes while walking the local greenway.  They are hard to see when they climb in the vegetation because their green color is the perfect camouflage.  These snakes often cross the paved greenway trail and that is where we can get good looks.  Recently we found a dead rough green snake, killed by a car, on the side of the road at greenway’s end.  The funny thing was, this green snake was partially blue in color.  It turns out that rough green snakes turn blue when they die.  The reason they turn blue after expiring gets into the mystery of color.

Vertebrates have a hard time making themselves green.  Unlike plants that make the green chlorophyll pigment to run photosynthesis, green snakes, lizards and birds must use two different means to turn green.  Their green color is usually a combination of yellow from a carotenoid pigment and blue produced from the structural elements of their skin or feathers.  This combination of pigment color and structural color works for green snakes, green lizards and green birds. 

Pigments molecules absorb certain wavelengths of light and that gives them their color.  Chlorophyll can be extracted from plants and still retain the green color.  Structural color is different.  It depends on the physical arrangement of small particles that refract certain wavelengths of light to produce color.  In many cases with structural color in animals, you need to view the subject from a certain angle for the color to be revealed. Eastern Bluebirds appear blue because tiny granules in their feathers refract blue light to the viewer.  In some light conditions bluebirds will appear black because the refraction does not occur.  Ruby-throated Hummingbird throats may appear dull from one angle, but as the bird turns a brilliant flash of red will shine out.  You cannot extract blue pigments from the feathers of bluebirds and you cannot extract red pigments from the throat feathers of hummingbirds.  Both these are examples of structural color.  

Rough green snakes have cells in their skin that contain a crystalline arrays of guanine, one of the components of nucleic acids.  The arrangement of the guanine crystals in these cells refract blue light.  Also in the skin of rough green snakes are cells that have yellow pigments that reflect yellow light.  Just like in an elementary school art class, yellow plus blue gives green. 

 

Dead rough green snake (Opheodrys aestivus)  with green regions and blue regions.

When a rough green snake dies, the yellow pigment begins to break down. The blue refracting crystals are more stable so the dead green snake gradually turns blue as the yellow pigment is degraded.  This was the state of the dead snake we found.  In some parts of its body the yellow pigment remained so it looked green in others the yellow pigment was lost and only the blue shone through. 

Alaska Connections

Diane and I recently made a twelve day trip to Alaska with a group of birders from North Carolina and Virginia.  On this trip we would revisit places from our expedition of 31 years ago and go to some new ones.  We saw lots of new land- and seascapes, a Canada lynx and a walrus, a Gyrfalcon and Bristle-thighed Curlews.  We also ran into some plants and plant-ish things I have written about recently in this blog.

Last month I wrote about alders growing near my home.  In Alaska, at Summit Lake on the Kenai Peninsula, the alders were in flower.  Alders in North Carolina flowered in early March but in southern Alaska, June is the flowering season.   The alder we saw in at Summit Lake was Alnus viridis ssp sinuata, the Sitka alder.  This alder is a scrubby tree and grows throughout Alaska, across the Bering Strait into East Asia, along the west coast of North American into northern California and down to the northern Rocky Mountains. The Sitka alder’s leaves are bright green with serrated margins.  The female catkins were green and the male catkins were brown, had already released their pollen but were still on the plant.  Sitka alder is an early colonizer of new land, beginning primary succession.  With global climate change, glaciers are receding at an increased rate.  When the retreating glaciers leave exposed ground, Sitka alders become established.  Their nitrogen-fixing, symbiotic bacteria enrich the soil paving the way for new forest to grow where the glaciers disappeared. 

Sitka alder (Alnus virdis ssp. sinuata)
with catkins of male flowers.

Sitka alder (Alnus viridis ssp. sinuata)
with female catkins

Haircap moss (Polytrichum strictum) gametophytes

The moist forests on the south side of the Alaska Range support a wide variety of mosses.  I wrote about North Carolina mosses  in April.  In Denali State Park we found thick and beautiful stands of Polytrichum strictum, the haircap moss.  This moss has a circumpolar distribution and extends into the lower 48 US states.  Clusters of gametophyte plants produce a green, star-pattern.  The sporophytes, the result of moss sex, have a little hairy cap at their tops, covering the capsule where the spores are waiting to be released. 

Haircap moss (Polytrichum stgrictum) gametophyes
with sporophytes

Kamchatka rhododendron (Rhododendron camtschaticum)
flowering on the tundra

Back in January I posted about lichens in Florida and North Carolina.  Out on the tundra of Denali National Park, where willows are inches tall and tiny rhododendrons (Rhododendron camtschaticum) produce large flowers, we found several species of lichens including the famous reindeer moss.  Reindeer moss is, of course, not a moss but a lichen, that symbiotic organism made of a fungus and an alga.  The lichens pictured here are Cladonia rangiferina (gray reindeer moss) and Cladonia fimbriata (trumpet lichen).  Lichens form much of the diet of caribou, Rangifer tarandus who endlessly graze as they walk the tundra.  Caribou are the same species as the old-world reindeer but have never been domesticated.  These large herbivores can find lichens even in winter.  Caribou use their sharp hooves to expose the lichens below the snow.  Unfortunately we did not see any caribou grazing the lichens of the tundra.   

Reindeer moss, the lichen
Cladonia rangiferina

 

Trumpet lichen Cladonia fimbrata

The differences between the Southeastern US and Alaska are striking.  There is a transition from subtropical to arctic with different habitats, climates, plants and animals. These areas are separated by a distance of more than 3000 miles and 30 degrees of latitude.  But the similarities between the Southeast and Alaska are profound.  Linked by biogeography and the evolutionary history of the inhabitants, the similarities were as striking as the differences.  

Basal Angiosperms I

Angiosperms, the flowering plants, appeared in the fossil record during the age of dinosaurs.  Dinosaurs and flowering plants coevolved for tens of millions of years.  When the dinosaurs were wiped out (with the exception of birds) 66 million years ago, flowering plants survived. There are more than 300,000 described species of angiosperms and they have a dizzying array of sizes, forms, structures and reproductive systems. 

The standard story, taught for two centuries, is there are two kinds of angiosperms, monocots and dicots.  This story says monocots have flower parts in multiples of three, parallel veins in their leaves and one cotyledon (the mono cot), that stores and transports nutrients to the plant embryo. Their counterparts, the dicots, have flower parts in multiples of four or five, net veins in their leaves and two cotyledons.  There are numerous other differences between these groups but in the field these three characteristics can usually distinguish monocots from dicots. 

Leaves of pawpaw (Asimina triloba) a basal angiosperm

Botanists knew about some weird flowering plants that did not quite follow those simple rules but new evidence has forced a major change in the classification of angiosperms.  Monocots are still monocots but evolutionary plant biologists have blown up the dicots, largely based on DNA evidence.  This new classification still has standard dicots but they are now called eudicots, the true dicots.  Another group of flowering plants show characteristics of both monocots and eudicots and are classified as basal angiosperms.  Basal angiosperms do have many characteristics of eudicots like the above-mentioned two cotyledons and net veins, but many have flower parts in multiples of three and their pollen structure is more similar to that of monocots. 

Basal angiosperms branched off early from the main flowering plant evolutionary line.  These plants have characteristics in common with some of the first flowering plants.  I like to image herbivorous dinosaurs munching on basal angiosperms.  Here are some of the primitive attributes shown by the basal angiosperms; flowers often have parts in threes or multiples of threes (a monocot-like trait), flowers show little differentiation between petals and sepals, they make numerous pollen producing stamens and numerous egg bearing carpels.   

You might think these primitive flowering plants, these living fossils are rare, but they are not.  It is true they make up only about 3% of flowering plants.  It is also true that one order of basal angiosperms contains only one species and grows only on the Pacific island of New Caledonia. But other basal angiosperms are common, well known and produce striking flowers. 

Florida anise, Illicium floridanum, is a basal angiosperm found in westernmost Florida and adjacent areas of Alabama, Mississippi and Louisiana.  This small trees have bright green, lanceolate leaves.  When crushed, the leaves smell of licorice or according to one source, freshly caught fish.  In spring Florida anise bears striking maroon flowers.  The flowers typically have flower parts in multiples of threes with an unruly batch of petals, a dense ring of purple stamens and in the center another ring of carpels.  Florida anise like many deep purple flowers is fly pollinated. 

The purple flower of Florida anise ( Illicium floridanum)

Pawpaw (Asimina triloba) is a basal angiosperm found throughout eastern North America.  This small tree grows in the forest under-story, along watercourses and in North Carolina flowers in early spring.  The flower is purplish-brown with three sepals and six petals.  The flower produces a disagreeable odor that attracts carrion feeding insects like flies and beetles.  Pawpaw has another interesting insect interaction.  It serves as the host plant of the zebra swallowtail butterfly, Protographium marcellus.  Female zebra swallowtails lay their eggs on leaves or branches of pawpaw; the caterpillars eat the leaves and retain toxic plant compounds when they metamorphose into the butterfly stage.  This gives the butterfly some protection from predators. 

Early spring flower of pawpaw (Asimina triloba)

Pawpaw fruit in summer

Zebra swallowtail butterfly (Protographium marcellus) feeding on Lantana camara.
Pawpaw is the host plant for the larvae of this butterfly. 

I will follow up with more about the compelling basal angiosperms in another post.

A Tale of Two Turtles

Diane was driving and I was riding shotgun on the Blue Ridge Parkway recently.  This beautiful, mountainous, winding road offers unparalleled scenery, opportunities for botanizing and wildlife viewing.  As we crested a hill, we saw an eastern box turtle (Terrapene carolina carolina) crossing the road.  Diane swerved to miss the turtle and pulled over on the narrow shoulder.  I jumped out to try to help the turtle cross the road.  As I closed to within about 20 yards of the box turtle two cars topped the rise and were bearing down on the plodding reptile. 

Eastern Box Turtle (Terrapene carolina carolina) in North Carolina

Eastern box turtles range from the Great Lakes and New England south to Florida and from the eastern seaboard to the Mississippi River.  Several other sub-species of the box turtle can be found in Florida, the Gulf coast and west to the Great Plains.  Box turtles have a high domed carapace that is distinctly marked with bright yellow.  Box turtles are called box turtles because their lower shell, the plastron, has a hinged section they can close and withdraw their head and legs for protection, as if in a box.  Box turtles females have yellow eyes while the males have fierce orange eyes. With the exception of tortoises, box turtles are the most terrestrial of North American turtles spending most of their time walking rather than basking on logs in a pond.  Box turtles have a varied diet that includes fruits, small animals and even mushrooms that are poisonous to humans.  Box turtles are potentially long-lived.  Captive box turtles have lived in excess of 100 years but most animals in the wild do not reach such an advanced age.  One of their major causes of death is automobiles.  Eastern box turtle populations have declined and the species now listed by the International Union for the Conservation of Nature (IUCN) as Vulnerable, one step from endangered. 

Back to the Parkway.  Two cars came over the rise, the first one straddled the turtle but the second car hit the turtle directly with left front wheel.  The sound of the tire crushing the turtle was awful, like a ceramic bowl full of bread dough dropped on the floor.  As soon as it happened, I wheeled around.  I did not want to see the aftermath.  The driver of the second car slowed, rolled down the passenger-side window and asked, “Did I hit something?” I had a one-word answer.  “Turtle”. 

A Clemson University researcher placed rubber turtles on a busy road and found 7 drivers out of 267 deliberately hit the fake turtles in one hour.  I cannot say if the death of the box turtle on the Parkway was intentional but these results of the study are disturbing. 

A week later Diane and I were in Florida visiting Merritt Island.  The island is a complex of marshes, woodlands and beaches that are protected by a National Wildlife Refuge, a National Seashore and the Kennedy Space Center.  Merritt Island is one of the premier birding spots in Florida and we were seeking the Florida Scrub-Jay.  Once again, Diane was driving and I was in the passenger seat when we spotted another Florida native, a gopher tortoise.  Once again, a reptile was crossing a road.  Once again, Diane pulled over and I jumped out to try to get a cold-blooded creature across a road.  A pickup truck was coming.

Gopher tortoise (Gopherus polypemus) on Merritt Island, Florida

Gopher tortoises (Gopherus polyphemus) live on the Coastal Plain of the Southeast from South Carolina to Louisiana and down the Florida peninsula.  Like box turtles, the gopher tortoises have a high domed carapace but it is gray or dark brown in color.  Gopher tortoises eat plant material like saw palmetto berries, grass and even the pads of Opuntia cactus.  Their front legs are massive with impressive claws and with rear legs described as elephantine.  Those front legs allow these tortoises to dig burrows where they can escape the heat or shelter from cold.  Other animals use gopher tortoise burrows including eastern diamondback rattlesnakes, armadillos and Burrowing Owls.  Like box turtles, gopher tortoises are classified as Vulnerable by the IUCN. 

Fortunately for this tortoise, the driver of the pickup truck stopped.  I scooped up the gopher and moved it to the other side of the road.  The tortoise dodged that truck.

I cannot stop for every reptile crossing the road.  But, when it is moderately safe, I will try to help turtles across.  Sometimes it works.