Learning to Love the Corn Earworm

Hale-Corn Earworm16-08-26

I fall in love the way some people drink coffee—quickly, all at once and at the slightest opportunity. This time, the object of my affection was a tiny tan moth, fluttering among a haze of purple tick-trefoil flowers in a power-line clearing in early evening. Every now and then it would alight on a blossom and feed before hovering away again, its wings fuzzy blurs of motion as it zigzagged through the field. I stalked it with a camera for several minutes, never removing my gaze from my quarry. It posed obligingly for me on a nearby stalk of tick-trefoil, its wings fully spread. As I held my breath and snapped the picture, I couldn’t help but notice its piercing green eyes. I was beyond infatuated—I was hooked. What was I looking at?

Zen master Fayan claimed that not knowing is most intimate, but the Greek philosopher Aristotle countered that all humans by nature desire to know. In this case, Aristotle won out. I posted the picture to an online community of naturalists and awaited their verdict, but I was unprepared for the truth. This beautiful moth and I had met before, under strained circumstances, and I hadn’t been so impressed with the results. The delicate creature that had captured my attention was actually the Corn Earworm (Helicoverpa zea) in an entirely different guise.

You’ve probably met the Corn Earworm, too, even if you didn’t know it at the time. It’s the caterpillar lurking at the tip of your newly-purchased summer sweet corn, fresh off the roadside stands, the proverbial serpent in paradise spoiling any illusions of perfection. Just like us, the Corn Earmworm loves those tender, developing kernels, and leaves a nasty trail of brown feces behind as it works its way down the cob.

Though unpalatable in their feeding habits, I’ve always found a few Corn Earworms a small price to pay for the sure knowledge that the corn in question wasn’t treated with synthetic pesticides. I don’t like them much, but I tolerate their presence, and I work to find ways to avoid them when possible. When I grow corn myself, I look for varieties that are naturally less susceptible to damage—like the heirloom ‘Strawberry Two Inch’ popcorn—and I’ve never had any problems with the earworms. (The European Corn Borer larvae, on the other hand, were not so easy to write off.)

More annoyingly, I find the Corn Earworm wriggling at the center of my best and juiciest tomatoes. There are all sorts of things that go wrong with tomatoes—early blight, late blight, cutworms, hornworms, blossom end rot—but the Corn Earworm is particularly vexing because you are so close to finally getting that ripe tomato in your mouth… until you notice the hole on the side conveniently hidden by foliage and the trail of frass smeared across the outside. Lovely.

Unlike most caterpillars, which tend to eat only one or two kinds of plants, and only those plants, the Corn Earworm is not a picky eater. Its common name shifts to reflect wherever you find it—the Cotton Bollworm, Tomato Fruitworm, Sorghum Headworm, and Soybean Vetchworm are just a few of its many incarnations— but by no means is it limited to those particular plants. In all of its larval incarnations, it feeds with gusto on developing fruits—and its fellow caterpillars, if it can get them—before dropping down to the ground to pupate in the soil.

After a rapacious juvenile delinquency, the adults settle down to relatively harmless existence nectaring on flowers. They are also, as I discovered, staggeringly beautiful in their own quiet way. But a female can lay thousands of eggs in her brief lifetime and perpetuate the cycle of destruction throughout the growing season. They don’t intend to vex me; it’s just an inevitable side effect of continuing their lineage. Once I knew them as adults, I could still squish the larvae when I found them, but I no longer mourned quite so much about the ones that got away.

Learning to love the Corn Earworm might seem like a challenge, but this story ends better than most of my love affairs these days. Unlike most species I fall for, it is abundantly common and ubiquitous wherever agriculture is practiced. Its populations are continually increasing despite vast quantities of pesticides sprayed to control them. Its larval form is an obnoxious pest in my plantings, but they are not going away any time soon. Now that I know what to look for, I find the adult Corn Earworm Moth nectaring on the garlic chive flowers in the evening, just outside my doorstep. The adult Corn Earworm Moth comes to sit with me on an urban patio four stories off the ground, where few other flying things dare to tread. In the age of the Anthropocene, the Corn Earworm will be with us always. It’s just as well that I’ve found a reason to love them.

A Prairie Home Companion

Prairie_Home-Companion

Grasses do not have a reputation for sexy among gardeners. In May, a chance encounter left me with dozens of leftover plants in need of a home, rejects from a sale at a local organization. It was immediately clear to me why they hadn’t sold: they were scraggly bits of green stuffed into plastic pots, primarily perennial bunchgrasses with a handful of obscure wildflowers thrown into the mix. For those who could read botanical Latin, however, the labels promised treasures: Virginia wildrye, wild quinine, purpletop greasegrass, scaly blazing-star, eastern gamma-grass, little bluestem, tall switchgrass, white doll’s daisy, redtop panicgrass. Just like at a cocktail party, I recognized most of the names, but I was hazy on the details; nevertheless, I recognized the call to adventure when I found it. And as it happened, I knew just the place to put them.

At first glance, the rain garden that came with my sister’s house was just a big hole in the ground. It wasn’t until we found the intake pipe, buried under rocks and clogged with debris, and connected it back to the gutters on the house that we realized it was a rain garden at all. Even though it was perfectly functional, catching and filtering runoff from the roof before it entered the creek on the edge of the property, it needed some work if it was going to be anything more than an eyesore.

The previous owners had their hearts in the right place, but landscaping was not their forte. There were some nondescript evergreen boxwood bushes around the edge of the pit that never flowered, a few irises in the late spring, and that was it for most of the year. In early fall, a cardinal flower (Lobelia cardinalis) popped up out of nowhere and made us popular with the local hummingbird before he migrated to Mexico. I stuffed some spindly leftover wild hibiscus I’d grown from locally collected seed into the pit and completely forgot about them. Life chugged along and the rain garden, well, just went with the flow.

I had no idea if the species from the plant sale were appropriate for a rain garden. But free plants and empty spaces bring out boldness in me. I planted randomly, mixing up species, colors and textures as best I could, until the entire pit was covered with tiny fluffs of green. They were up against the heat of summer and my Darwinian approach to gardening: whatever survived would do it on its own merits, without much coddling from me.

When I came back in August after months on the road, the barren pit had been transformed into a lush, overgrown jungle courtesy of a series of conveniently timed thunderstorms rolling through in the afternoons. The spindly hibiscus had managed to survive after all, the cardinal flower had come back for a second round, the wild quinine blooms had flopped over from their own weight, and the grasses had swelled both horizontally and vertically into massive clumps. Some had even sent out flowering plumes. “It needs to be mowed,” my father quipped. Meanwhile, as a student of botany, I saw the rain garden through new eyes now that the plants had matured. Inadvertently, unintentionally, almost completely by accident, I had re-created a patch of one of the state’s rarer ecosystems in my sister’s backyard: the Piedmont prairie.

Prior to European settlement in North Carolina, the uplands were patchworks of shady forest and open fields, grazed by bison, elk and white-tailed deer. Prairie meadows formed in areas where the soil was too poor to support trees, maintained by periodic fires. Unlike the annual grasses that make up most modern lawns, the Piedmont prairies were dominated by perennial bunchgrasses and specialized wildflowers. Once Europeans arrived, however, they cleared the land for agriculture and fires were suppressed. The patchwork prairies vanished, except along roadsides and utility right-of-ways where periodic mowing and spraying kept the trees from taking over again.

These days, the few remaining prairie remnants look remarkably ordinary—just another overgrown field—until you take a closer look within the sea of green. Those seemingly random species I had acquired from the plant sale were actually prime representatives of this fragmented and vanishing ecosystem. None of them were rare in and of themselves—but having all of them together in one place was unusual, a hearkening back to a not-so-distant past.

My tiny patch of prairie isn’t a perfect representation of what used to be here—we’re heavy on grasses, but missing many of the charismatic wildflowers like smooth coneflower and starry rosinweed that are now significantly rare in the state. That said, there’s only so many species you can cram into a few square feet, and the few anomalies grandfathered in just add to the garden’s own special character.

Ironically, my father was right—periodic mowing (or perhaps scything, in our case) is the way to go to maintain a prairie in the long run. Unlike the lawn grasses that grow scruffy after two or three weeks, though, the prairie can get by with one mowing every two or three years, unless an errant bison wanders by and trims it for us. Until then, I sit out on the porch and survey my tiny empire of grass. In the evening, after the afternoon thunderstorm passes through, I swear I can see them growing.

Graze On

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Goats in landscape management at German Highway. Photo by Spielvogel licensed under creative commons by Wikipedia.

I have always learned that invasive species come into an area due to imbalances in the ecosystem, such as a lack of natural predators or loss of nutrient resources necessary for native vegetation. Yet, the only solutions I ever heard were very unnatural. We could spray chemically engineered herbicide over landscapes, bring in heavy machinery to destroy anything in its path, or personally rip all the unwanted plants out of the grown. So, what about a more natural method of removing invasive plants? Thankfully, they have arrived.

Goats are the natural predators of many common North American invasive plants and have been eating them for thousands of years. Goats have evolved naturally grazing on many of the troublesome invasives that are dealt with today, such as, kudzo from East Asia or Phragmites australis from Europe [1]. The goats are so efficient because the seeds of the plants are often crushed in the goats’ grinding mouths and multi-chambered stomachs [2]. A herd of 35 goats can consume roughly half an acre of thick vegetation in only 4 days! [3]

Machinery and herbicide removal often creates additional disturbances in ecosystems. Equipment may trample or remove native, sensitive species as it takes out invasive species and herbicides can contaminate water and soil. Herbicides can also be toxic for insects who live on or eat plants, and may cause cascading imbalances in the food chain. However, the goats are able to restrict their feeding and removal to specific problems areas with fences, without leaving harmful chemicals. Once one area is done, the fences are moved and the goats graze on [1].

I often struggle to pick a side when it comes to invasive species removal. Do we pull everything out, just to see them return? Or, do we let nature take its course and leave the invasive species there? What designates a species as “invasive”? How long does a species need to be in the area to be considered “native”? But, by using goats to control invasive species, balance is being brought back into the ecosystem and the species are removed without harming native plant or animal species. Besides, I’m sure the goats are happy with the decision; they are being paid to eat multiflora rose and bittersweet all day! [1]

Watch them work! https://www.youtube.com/watch?v=Z1iZ2JkJrnc#t=69

Mary Kate Lisi is a rising UVM junior Wildlife Biology and Environmental Science double major taking part in a undergraduate field naturalist pilot program this summer.

 

[1] http://www.vtinvasives.org/news/goats-take-notorious-invasive-species

[2] http://www.eco-goats.com/why-goats.shtml

[3] http://www.bbc.com/news/magazine-30583512

If you give a monarch some milkweed

                                       1280px-Monarch_Butterfly_Danaus_plexippus_Feeding_Down_3008px Monarch caterpillar photo by Derek Ramsey and licensed under creative commons by Wikipedia.

Monarchs are one of Vermont’s most recognizable butterflies. Their distinctly patterned orange and black wings are both well known and loved; making them the state butterfly of Vermont, as well as six other states [1]. There are many commonly known facts about monarchs and their fondness for milkweed, but there are also many misconceptions.

One commonly mistaken belief is that monarch butterflies eat solely milkweed. Rather, it is the caterpillars that rely on the milkweed vegetation for food. The butterflies lay their pinhead-sized eggs underneath milkweed leaves as the foliage is the one and only plant that monarch caterpillars will eat. Meanwhile, the adult butterflies are often seen sipping on nectar from a variety of flowers.

Many people also think that if there is milkweed around, then monarchs should then be thriving. Young caterpillars actually have a relatively low survival rate when eating the milkweed, only about 3-11%. About 30% of larval losses are due to the mandibles of the caterpillar getting stuck in the sticky latex glue. Monarch researcher Stephen Malcolm wrote that a caterpillars first bite into the milkweed is “the most dangerous thing the ever do in their life”. However, some caterpillars have developed strategies to protect themselves from the latex. Some will chew through the midvein of the leaf to cut off latex flow to the area they are eating [2]. Every time you see a monarch caterpillar metamorphose, it has beaten the odds of survival.

Another misconception about milkweed is that it is only good for monarchs. In reality, there are actually dozens of other species that feed exclusively on milkweed as well, including many different types of the milkweed beetle, the cycnia moth, and the milkweed tussock moth [2]. There are also many pollinators such as bees and butterflies that use the nectar from milkweed as a food source, this in turn attracts other predators to the plant, which then attracts scavengers, making milkweed a valuable plant that contributes to diverse ecosystems.

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Swamp milkweed photo by Derek Ramsey and licensed under creative commons by Wikipedia.

It is often assumed that mowing milkweed is harmful to monarchs. However, it is actually the opposite. The chemicals given off by milkweed’s toxic latex glue allow the adult butterflies to help locate the plant and then lay eggs on it. Caterpillars absorb the toxins and become poisonous themselves. When a milkweed plant is cut down, it grows back with an even higher concentration of latex glue, so naturally butterflies tend to prefer milkweed that has been regrown. Here in Burlington, a field off of the bike path, just north of North Beach, is known as monarch meadow. The field is currently being mowed and managed to encourage milkweed regrowth and help provide a breeding area for migrating monarchs.

Stop by the field during the late summer and you might be lucky enough to catch a glimpse of the migrating monarchs!

Ben Fisher is a rising UVM senior studying Environmental Science and taking part in a undergraduate field naturalist pilot program this summer.

 

[1] Official State Butterflies. Retrieved August 02, 2016, from http://www.statesymbolsusa.org/symbol/vermont/state-insect/monarch-butterfly

[2] Eastman, John (2003) The Book of Field and Roadside Open Country Weeds, Trees, and Wildflowers of Eastern North America, Stackpole Books.

 

Newt Tales

Photo by Griffin Dahl, around a dried up vernal pool in Raven Ridge Natural Area.

While hiking below a vast dolostone face within the Raven Ridge Natural Area on the border of Hinesburg, Monkton, and Charlotte, a bright orange figure caught my eye waddling along a patch of leaf litter. The area was most likely a dried up vernal pool, a seasonal breeding pool for amphibians, covered thoroughly with wet leaves, fallen snags and mossy cobble. Captivated by its silent presence and clumsy strides, I was in awe of the fact that I had never notice this gentle forest dweller in the past. This adolescent salamander was an Eastern Newt, a complex amphibian migrating between Vermont’s waterways and the moist crevices of a typical Northern Hardwood Forest.

Breeding

The breeding process for an Eastern Newt begins during early spring, as the egg filled female searches for a mate near potential breeding ponds. The females are attracted to a male’s spots and appealing pheromones that waft through the water as they wiggle their broad tails. Males then drop sperm packets in the water, awaiting the female to pick up these packets with their cloaca, a cavity located at the end of amphibians digestive tract, in order to fertilize her eggs successfully [1]. Finally, a female will lay her eggs one at a time and scatter  them upon aquatic plants, leaving them to survive independently for around a month or two before hatching [2].  

Incubation/ Larval Stage:

These 200 to 400 jelly covered eggs now go through a 2 to 6 week incubation stage before hatching, followed by their larval stage lasting another 2 to 6 months. During this stage larvae are brownish-green and develop gills, growing to about a half inch in length. These larvae feed on small aquatic insects and crustaceans until they leave their birth ponds into the summer, lose their gills and start their first terrestrial stage of life [1].

Eft/ Juvenile Stage:

At last, the larvae develop into their juvenile, terrestrial stage where they are known as Red Efts. Efts use their bright orangish-red coloration to warn predators of their poisonous skin secretions. But don’t fear, handling these creatures is perfectly safe. Red Efts grow up to 5 inches in length and reach sexual maturity around 3 years old [4]. These juvenile efts feed on small invertebrates like snails, springtails and soil mites. Eastern Newts can survive in the eft stage for up to eight years before maturing into their adult stage so long as their habitat is sufficiently moist for survival [3].

Mature Stage:

As efts reach their mature adult stage, their skin darkens reaching a brownish-yellow or green coloration, their tails flatten, and their underbelly brightens to a yellow color with black spots. They now return to aquatic environments, searching for temporary and seasonal habitats anywhere from small lakes to marshes, though mature newts prefer abandoned beaver ponds [4]. Here they feed on immature aquatic insects, larvae and other amphibians breeding in nearby vernal pools, continuing the life cycle of the Eastern Newt for further generations to come [2]. The Eastern Newt is a delicate and often overlooked species found throughout the eastern United States, so remember next time you’re walking in the woods, especially in the rain, keep your eyes peeled for orange flashes under logs and rocks… it might just make your day.

Griffin Dahl is a rising UVM junior studying Natural Resource Ecology and taking part in a undergraduate field naturalist pilot program this summer.

 

[1] http://www.vtfishandwildlife.com/cms/One.aspx?portalId=73163&pageId=149749

[2] http://www.nhptv.org/wild/easternnewt.asp

[3] http://www.fcps.edu/islandcreekes/ecology/eastern_newt.htm

[4] http://www.reptilesmagazine.com/Frog-Amphibian-Species/Eastern-Newt/

 

What’s In a Name When It Comes to Moths?

toothed somberwing

National Moth Week has come and gone, but it’s still a great time to get outside and look for moths. Why bother with moths, you ask? Well, they come in a dizzying variety of colors, shapes and sizes, and occupy just about every terrestrial habitat in North America. They have fascinating life cycles and strategies for survival, lurking literally behind every leaf and branch. Many of them come to electric lights at night, so you can sit back, relax, and wait for them to come to you (a plus for fieldwork). But there’s another reason to study moths, something that rarely gets mentioned in the literature – their amazing names.

Where else on a summer night can you encounter the Cynical Quaker, the Unarmed Wainscot, Drexel’s Datana. the Georgian Prominent or the Toothed Somberwing (photo of this last moth above)? Aren’t you intrigued by the existence of the Confused Haploa, the Girlfriend Underwing, the Honest Pero, and the Friendly Probole? What’s the story behind the Shattered Hydriomena, the Retarded Dagger, or The Laughter? How can you sleep at night when the Black-Blotched Schizura might be resting on your porch? What about the Goat Sallow, the Abrupt Brother or the Grateful Midget?

There are moths with more prosaic names, of course. The Reed Canary Grass Borer, for instance, leaves precious little to the imagination. Others, like the Spiny Oakworm Moth or the Yellow-Necked Caterpillar Moth, are named for their juvenile appearance, and bear little resemblance to their former selves. Many species are named for the plant their caterpillars feed on, or some youthful quirk of habit, like the Pecanleaf Casebearer and the Basswood Leafroller. Other species go by multiple aliases, depending on their age: Woollybear Caterpillars grow up to be Isabella Tiger Moths, and Hickory Horn Devils mature into the elegant and reformed Regal Moths.

Other names invite questions. Is the Dubious Tiger Moth any less trustworthy than its fellows? What happened to the Once-Married Underwing? Why is it not the Divorced Underwing instead? (That’s different, of course, from the Widow Underwing, which is an entirely different species.) Is the Nameless Pinion actually nameless? What is the Grieving Woodling’s problem, and is the Disparaged Arches moth really that bad?

Clearly, lepidopterists have a lot fun (and more than a few beers) when it comes to moth names. It’s time for the rest of us to catch up on the action. Fortunately, it’s never been easier to learn about moths. Flick on a light switch in the evening and see who shows up. Take pictures with a camera or smartphone and post them online to websites like BugGuide or iNaturalist for identification suggestions and tips. You’ll be amazed by how much is out there once you start looking.

If you live anywhere between Maine, Minnesota, Iowa and Virginia, you can flip through the excellent Peterson Field Guide to Moths of Northeastern North America by David Beadle and Seabrooke Leckie, which has color photographs of 1,500 of the most charismatic species you’re likely to encounter. Unlike old-school entomology displays, where dead moths are pinned with their wings spread, the Peterson Guide features live moths in their characteristic poses, just as you see them in the field. The endpapers have silhouettes of the family groups, so with a little practice, you’ll be distinguishing your Tiger Moths from your Tussock Moths and your Prominents from your Geometers, just like the pros. Similar volumes for the rest of the continent are expected to follow.

Sure, most people are excited when a charismatic megamoth like a Luna Moth shows up in their lives. The bright colors of the Showy Emerald or the Pandorus Sphinx will make even the most jaded naturalist’s night. But I’m always happy to see a Dusky Groundling or the Cloaked Pug, however drab and grey their markings. The Beggar and The Neighbor (not to mention the The Slowpoke) will always have a place in my heart. Even a Simple Wave is a cause for celebration. My field notes sound like I’m auditioning for comedy night at the local club – and that’s before The Bad-Wing shows up. And I can promise you this: as a student of moth names, I will never, ever be bored.

Vermont’s State Musician

HermitThrush-PFEIFFER

 

“Is that a bird?” asks one of my fellow Field Naturalist Interns, as we stand on an outcropping at Raven Ridge Natural Area on the border of Hinesburg, Monkton, and Charlotte, Vermont. When I told him that the song he was hearing was that of the Hermit Thrush he said that he had “never heard a bird sound so much like music”. I had never really considered the musical elements of birding before this comment and then felt compelled to look into the compositional stylings of the Hermit Thrush.

This medium-sized member of the genus Catharus (which also happens to be the state bird of Vermont) sings a song that is perhaps that most magical string of notes I have ever heard. Being somewhat of a musician and much more of a birder, I love listening to the song of the Hermit Thrush with its melodic, tumbling trills, like a flute harmonizing with itself. According to a number of auditory studies, the notes of the song of the Hermit Thrush are related to each other by pitch ratios that differ by simple integers of harmonic notes [1]. This discovery highlights the fact that the song is more similar to music produced by humans than to the songs of other birds that have also been studied in this way. It is also noted that certain harmonies produced by the Hermit Thrush are in line with those made by human music [2]. On top of all this musical jargon, it has also been discovered that this bird could be capable of producing other notes in its song, meaning that the species chose to sing in such an ethereal harmony.

You don’t need to have a musical background to appreciate the sounds of nature, the birds singing, the creaking of young trees as they sway in the wind, the croaking of a distant frog, or a stream gurgling and dripping down a mountainside. Among all of these sounds, however, nothing resembles music quite as closely as the song of the Hermit Thrush.

Hear it for yourself! https://www.allaboutbirds.org/guide/Hermit_Thrush/sounds

Emily Hamel is a rising UVM senior and Wildlife Biology major taking part in a undergraduate field naturalist pilot program this summer.

 

[1] https://www.newscientist.com/article/dn26498-thrushs-song-fits-human-musical-scales/

[2] http://www.smithsonianmag.com/science-nature/birds-songs-share-mathematical-hallmarks-human-music-180953227/?no-ist

 

The Hidden Gems of Lake Michigan

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A professionally polished Petoskey stone, similar to what you would find for sale in shops throughout Michigan.  The diagram in the corner indicates scale. Photo by Dr. Mark Wilson of the College of Wooster, Ohio, via Wikimedia Commons.

This summer, transport yourself to the eastern shore of Lake Michigan, near the town of Petoskey, and perform a geological magic trick. Take a chunk of limestone on the beach – bland, grey and completely featureless – and dip it into the lake. Stare into the translucent depths at your chosen stone and watch distinctive hexagonal patterns emerge on the surface. But a funny thing happens when you pull the stone out of the water and let it dry in the sun – the markings abruptly vanish! What’s going on here?

As you might have suspected by now, this is no ordinary piece of limestone. Instead, you’ve stumbled across a Petoskey stone, beloved by geologists and beachcombers alike. Like all magic tricks, however, there is indeed a simple explanation for the vanishing act, impressive as it appears on first viewing. In this case, our mysterious rock’s origins in the distant past owe just as much to the animal as the mineral.

Four hundred million years ago in the Devonian era, Lake Michigan did not exist, but there was no shortage of water in the area. A wide, shallow tropical sea covered the area, home to a diverse array of bizarre-looking marine life: horseshoe crab-like trilobites, spiraling ammonites, brachipods and other shellfish, the first jawed fishes, sprawling crinoids and crustaceans. (When T.S. Eliot has J. Alfred Prufrock mutter, “I should have been a pair of ragged claws / Scuttling across the floors of silent seas,” he was probably thinking of the Devonian.)  It was also a golden age for coral, including one family – now extinct – known as rugosans, or “wrinkled,” on account of their distinctive appearance.

While many of these rugosan corals were solitary polyps, other species opted for a more communal approach. They massed together, forming vast reefs similar to the ones we see in our own era off Hawaii or Australia.  One of these colonial coral species, Hexagonaria pericarinata, was particularly abundant around the future home of Petoskey, Michigan. As the scientific name suggests, these corals were highly symmetrical, with each animal forming distinctive six-sided walls as it tried to occupy the maximum possible space against its many neighbors. (Unlike the rigid chambers you see in honeycombs, you’ll often find five, four, or even three-sided corals who just couldn’t grow up fast enough to compete with their more aggressive counterparts, or asymmetrical hexagons formed by polyps that got “squashed”.)

When individual polyps died, others grew on top of them and the cycle repeated. Eventually, whole reef conglomerates were buried by ocean sediments in the shifting seas. Time and pressure transformed the coral and sediment matrix into calcium-rich limestone, the coral polyps preserved as flattened outlines of their former, three-dimensional selves in the rock. Each polyp’s alimentary canal became a dark speck that forms the “eye” of each hexagon; the lines that radiate outward from the center mark where tentacles were located.

Fast forward to twelve thousand years ago in the Pleistocene. The tropical ocean vanished long ago, replaced by bare stone and a wall of glaciers three miles high. As the glaciers advanced and retreated, they scoured the bedrock, kicking up chunks of the limestone reefs and gouging out the depression that would fill with meltwater and become Lake Michigan. Rounded and sculpted by water, the fossilized coral fragments were moved by centuries of robust freeze-thaw cycles southward in the lake, occasionally washing up on beaches tens or even hundreds of miles away from their original site.

Dubbed “Petoskey stones” because of their abundance on the beaches and bedrock of Petoskey, Michigan, these stone corals are ubiquitous in gift shops throughout the state. You can find their likeness on a number of “Petoskey tchochkes” including magnets, bumper stickers and t-shirts, so residents and tourists alike can proclaim their love. As a sign of their distinctive popularity, Petoskey stones have been the official state stone of Michigan since 1965. They remain a source of local pride and a prize find during any lakeside stroll. Most stones you find on the beach are tiny, but huge storms can wash five, ten, or even twenty pound specimens out of the lake overnight.

Why are they easier to spot in water? The contrast between the slightly lighter crystals of fossilized coral body (calcite) and the surrounding stone is greatest when wet, making them easiest to detect underwater or well within the splash zone of the lake. (Further away from the lake shore, less discriminating rockhounds opt for spittle or other body fluids as a way to test their finds.) Some stones will naturally keep their appearance without water or any further treatment, but most of the stones available for sale have been professionally polished to ensure that the distinctive hexagons remain visible even when dry.

You can replicate the same look on stones you find on the shore with some fine-grit sandpaper, elbow grease, and a little toothpaste and velvet cloth for polish. Limestone is soft and easily eroded, so a little bit of effort goes a long way – a conventional rock tumbler is overkill, converting beautiful stones into a dusty pile of sediment. But maybe you’ll keep any stones you encounter in their natural state, tucked away in your pocket, ready to perform a magic trick of your own.

A Passionate Pollinator

bee

A typical maypop pollination sequence in action. Note the shiny abdomen of the carpenter bee, and the oblong yellow anthers smearing pollen over the bee’s thorax. The round green stigmas, slightly above the anthers, will be jostled when the bee is preparing to move to another flower. Photo by the author.

Summer blockbusters at the multiplex are big and bold, but equally dramatic spectacles are happening outside as plants send up blooms to attract insect pollinators. While sunflowers and zinnias command quite a following, and anise hyssop and bee balm have their charms, the best show in town right now in central North Carolina is at the maypop—also known as the purple passionflower—hands down.

Colorful and vivid, with a curtain of tye-dyed strips surrounding a pillar of five anthers perched below three ovaries, any of the five hundred plus species of passionflower would fit right into a bouquet designed by Dr. Seuss. Some see the flowers as strangely clock-like; others view it as living metaphor full of religious symbolism. Despite its exotic appearance, however, the delights of passionflowers aren’t limited to the tropics. Five species can be found growing throughout the southeastern United States, and the maypop (Passiflora incarnata) is one of the hardiest of the lot, ranging as far north as Pennsylvania in the wild.

Unlike many native perennials, which need specialized environments in order to thrive, the maypop is not fussy about its living space. It’s aggressive and vigorous, flourishing in full sun and disturbed areas, even in years with little rainfall. It clamors up over other plants in a race to get ahead, twining tendrils and pulling no punches, to the point where it’s occasionally listed as an agricultural weed. It can grow as much as fifteen feet in a season before dying back to the ground with the frost. This drive to survive at all costs, coupled with its showy purple and white blooms and edible fruit, has made it a beloved staple of Southern gardens. And with it come the pollinators.

Eastern carpenter bees (Xylocopa virginica) look and act much like their bumblebee cousins, with a few twists: bigger, buzzier, and boasting black and shiny abdomens. Aside from the occasional misstep of burrowing into wooden structures, they rarely bother humans. Like all bees, they are important pollinators for flowers—except when they “cheat” by nipping flowers at the base to get a quick hit of nectar.

The maypop, however, has an ingenious mechanism to foil cheaters. Instead of having a curled base for nectar storage, all of the good stuff is located at center of the flower’s disk. In order to reach it, however, the bee has to brush against at least one of the five stamens—conveniently located just the right height for a carpenter bee—which smear pollen all over the bee’s head. Once the bee is finished at the first flower, it will have to rub up against the receptive stigmas of the next flower in order to drink more nectar, thus ensuring successful pollination. I’ve never seen any of them stop at just one flower! Occasionally, a tiny wasp or a Japanese beetle might slip in to steal some nectar, but the vast majority of insects I see on maypop flowers are carpenter bees, obliviously pollinating away while they gorge on nectar.

fruit

Not ripe yet…. but getting there! Photo by the author

And thus arises the other wonder of the maypop—namely, its fruit, which closely resembles its commercially grown tropical cousins in size and taste. You may think you’ve never tasted a passion fruit, but guess again—its distinctive flavor adds a kick to the popular fruit drink Hawaiian Punch. The egg-sized fruits—technically berries—fall to the ground when ripe, and can be eaten out of hand. They can also be used in jams and jellies, although I’ve never met anyone who’s managed to make it that far with them.

Dinner and a show—who could ask for anything more on a hot summer day?

Southern Comfort

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The Southern magnolia flower in bloom. Photo by DavetheMage. Image licensed under creative commons by wikipedia.com.

The grande dame of its family, the southern magnolia dominates the landscape. There is simply no overlooking its stately elegance, especially when it is in full bloom. Bearing flowers as wide as your face—worthy of the epithet grandiflora, “big-flowered,” indeed—a southern magnolia is no mere tree. A southern magnolia is an experience.

Let’s start with the blooms. Following a design ancient by evolutionary standards, they are similar in structure to the first flowers that appeared in the Jurassic era millions of years ago, a testament to success. Large simple petals, pearly in color and texture, fold over a bizarre-looking yellow cone-like structure at the center. Yellow stamens fall like matchsticks from the base of each cone—actually compendium of simple pistils—and collect in the folds of the petals. Once the flowers have been fertilized, the petals fall back in a brown and crinkled heap as fleshy red fruits dangle on tiny white threads from the now-green and black cone. Until that happens, though, the scent is heavenly—alternately described as lemon, citronella, or jasmine—as an enticement to its beetle pollinators.

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The fruit, seeds and cone in all their bizarre glory. Photo by Pmsyyz. Image licensed under creative commons by wikipedia.com.

Meanwhile, the rest of the tree is equally impressive. The leaves are stiff and papery, green and waxy above and fuzzy brown velvet beneath. Typically boasting a single trunk, each tree stretches into a classic pyramid, broad at the base and narrowing to a single point at its apex. Given enough time and space to reach mature size, each magnolia tree becomes its own island, its lower branches hovering just above the ground, the evergreen leaves above form a dense canopy under which nothing else can grow. Blocking out the sounds and view of the world outside, each tree becomes a miniature oasis. A grove of mature trees forms a graceful archipelago—truly a sight to behold. Even in winter, the southern magnolia bears the occasional snowfall or ice storm with grace.

With the possible exception of live oaks, no trees are more evocative of the archetypal South than the southern magnolias. Yet they are true natives only to a swathe of the southern Carolinas, Georgia, Alabama, Mississippi, and Florida. Known colloquially as “bull bay,” they join their cousin Magnolia virginica, the sweetbay, and the unrelated redbay and loblolly-bay to grace the swamps and pocosins with their presence. Left to their own devices, they would never have made it further into the uplands. Fortunately for gardeners everywhere, the southern magnolia thrives outside of its natural range, even when pushed to its limits. One such specimen can be found in Burlington, in the courtyard of Marsh Life Science building on the University of Vermont campus, where sheltered walls and a south-facing aspect create a microclimate warm enough for this southern tree to survive harsh New England winters.

Moreover, the southern magnolia is versatile in the human-dominated landscape: I have also seen it growing as a street tree in Monterey, California and lining parking lots and new developments in Cary, North Carolina. However, most of the trees used in the modern horticultural trade are dwarf cultivars that will never reach the width and stature the species is capable of. Although my heart is gladdened to see them, I cannot help feeling wistful, as if something important has also been lost.

Climbing those older, giant trees was an essential staple of my childhood. The wide, thick limbs were easy to scramble up with the ease of a squirrel, offering real height and perspective. For a time, I was removed from the cares of the world and fully immersed in the world offered by the trees. Attending college along the Chesapeake Bay in Maryland, the southern magnolias grove tucked away in a sheltered courtyard soothed my soul during times of anxiety and change. The arbiter of student discipline, the Assistant Dean, had an office directly facing those trees, so I never found the courage to climb them. Still, I valued those trees for the reminder that I was not too far, ecologically speaking, from home.

It’s May now, and the southern magnolias are blooming again in the gardens of my hometown in North Carolina. When I breathe in the scent of its blossoms, I am in my childhood again, that long golden summer where anything is possible and no height is unattainable.

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