Wandering down Piney Woods Church Road late this afternoon, I passed a driveway all aglow with moss sporophytes, with their globe-like capsules perched atop stalks, called seta, reaching high above the leafy gametophytes. (That sentence, I realize, begs a lesson in the moss life cycle, but I will instead refer curious readers here.) The yellow-green of this sporophyte carpet betokens the impending arrival of spring (although not before another cold spell visits the region this Wednesday).
Sometimes nature really surprises us. We naturalists fill our shelves with field guides, and their minds with Latin names for local species of animals and plants. We venture into the woods looking for the first spring ephemeral wildflower in bloom, and listening for the first call of a red-wing blackbird at a nearby marsh. After a bout of rain, we take pleasure in the more unusual pastime of identification and, for the more daring, consumption of various fungi.
But sometimes we chance upon something so foreign, so peculiar, that it truly humbles us. All we can do is fall back on Shakespeare’s famous remark that “There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.” The cedar apple rust gall definitely fits into that category.
For all the field guides out there, precious few are devoted to plant galls. These strange constructions of living plant tissue, formed in response to invading parasites such as insects and fungi, somehow fall between the cracks. They are neither healthy plant specimens nor parasites themselves, but instead a product of the two, in which a parasitic organism somehow takes control of the plant’s growth and warps it to its own ends. Often, the gall serves as home for a developing insect, and protection from predators as well. In the case of the cedar apple rust gall, th gall is part of the bizarre fungal life cycle.
The cedar apple rust gall receives its name from the fact that the fungus responsible, Gymnosporangium juniperi-virginianae, lives alternately on cedars and apple trees. Fungal spores invade a eastern red cedar (Juniperus virginiana) and live within the host plant’s tissues for up to two years. During that time, they cause brown galls to develop on the tree. These galls grow to a couple of inches in diameter and then, after a series of spring rains, they burst open, releasing gelatinous orange tendrils. The tendrils, in turn, form and release spores to be carried up to three miles by the wind.
But these spores do not re-infect red cedar trees. Instead, they invade apple trees, where they produce yellow and orange lesions on leaves and fruit. Black pimple-like bodies form in these lesions and release a sticky substance that attracts insects. In a peculiar parallel to pollination, the insects carry fungal reproductive cells from one rust spot to another, fertilizing the fungus. The fungus then grows through the infected apple leaf, forming reproductive structures that release new spores that invade red cedars, continuing the cycle.
The cedar oak gall is a serious disease of apples. As such, I suspect it is quite familar to most orchardists. But to this naturalist, the sight of its bright orange tendrils was most unexpected — alien, even. It was a pleasant surprise, warding off any incipient complacency. There is still a lot out there left to discover. A 2007 field guide to galls of California and the Western US (available here), which appears to be the only gall guide in print for anywhere in this country, included thirty-five galls “new to science”. That figure represented more than ten percent of the galls covered in that book. Amazing.
This article was originally published on April 6, 2010.
After a stunning display of orchids, tulips, daffodils, and crocuses at the Atlanta Botanical Gardens yesterday, I returned to Piney Woods this afternoon having difficulty making the shift back to a drab landscape still mostly wearing its winter garb. Apart from the everlasting daffodils (the blossom I first photographed weeks ago is still going strong), the only flowers blooming at the moment are minute ones. There are the maple blossoms yet, and then the flower garden of early weeds at the confluence of Piney Woods Church and Hutcheson Ferry Roads. There, I mostly found more hoary bittercress and the ubiquitous henbit. It took me a few minutes to discover something new: yet another tiny white flower, this one clustered atop at tiny stalk. It is a member of the genus Draba, and almost definitely Draba brachycarpa, shortpod whitlow grass. Its common name, alas, comes from a swelling near a toenail or fingernail (called a whitlow), for which the juices of this plant are supposedly beneficial in treating. Even its Latin name of Draba does not strike me as particularly poetic. However, it was a tiny flowering annual of this very genus that inspired the renowned early ecologist Aldo Leopold to write (in A Sand County Almanac), “He who hopes for spring with upturned eye never sees so small a thing as Draba. He who despairs of spring with downcast eye steps on it, unknowing. He who searches for spring with his knees in the mud finds it, in abundance…. Draba plucks no heartstrings. Its perfume, if there is any, is lost in the gusty winds. Its color is plain white. Its leaves wear a sensible wooly coat. Nothing eats it; it is too small. No poets sing of it. Some botanist once gave it a Latin name, and then forgot it. Altogether it is of no importance — just a small creature that does a small job quickly and well.”
Earlier today, I visited a public garden near my home. I was there in the late afternoon on a Friday, and the grounds were nearly deserted. Squirrels raced about, carrying bits of trash or snacking on the various garden plants. I also heard — and saw — numerous cardinals. The squirrels posed for me and the cardinals stayed put long enough to turn and look at me once or even twice. By comparison, the Piney Woods Church Road wildlife is exceedingly skittish. The other day, I glimpsed my first cardinal along the roadway, but it vanished long before I could bring it into focus with my camera. I have seen a few squirrels, but always from a distance, and always racing away from me as rapidly as possible. Their urban cousins are so much more affable with regard to being photographed. I suspect this is, in good part, because of all the food (human litter and various plants) available in the gardens. I suspect people try to feed the squirrels from time to time, too. Whatever the cause(s), the result was some charming images.
Resurrection fern (Polypodium polypodioides) is among my most favorite ferns. It spends much of the year looking like dried-up leaves clinging to a tree branch. After rainfall, it magically transforms itself into a vibrant green, luxurious fern layer festooning tree limbs. Resurrection fern is an epiphyte, gaining all the nutrients it needs from what is in the air and what might collect on the outer surface of the tree bark. It does not harm its host in any way. This photograph was taken among the pecan trees, about halfway down Piney Woods Church Road. I dedicate this image to Fern’s Market in Serenbe, which has provided me with a marvelous haven for reading and hanging out since it first opened in 2012.
On yet another rainy, wintery afternoon, with the air temperature struggling to rise above 40, and the wind chill in the lower 30s, I started off down Piney Woods Church Road hoping to discover something new — some further omen of spring’s return. I was delighted to find, almost immediately, more red maples in bloom — this time, a couple of trees growing near the intersection with Rico Road. I snapped a number of photos of them. Upon returning home, I was most drawn to my images of this particular cluster of flowers. Alas, a dead stalk of some kind of large weed in the background provided an annoying distraction in every single shot. So I broke with tradition, trudging back a second time to take the photograph below.
On a raw gray day, with the temperature hovering in the mid-40s, I compelled myself to seek out more signs of spring’s eventual arrival. I spent perhaps fifteen minutes endeavoring to photograph a tiny bluet (Houstonia pusilla), a native wildflower so minute (a few millimeters across, on a stem a couple of centimeters high) that it is a challenge to capture even with a macro lens. The result, though, is worth the effort: a photograph with a vibrant splash of violet color, in the midst of a dark and drab late-winter afternoon.
The daffodils are still in bloom along Piney Woods Church Road, and more seem to be popping up every day. I find them intriguing, because even though they are so commonplace, they have an unusual feature, the corona, whose origin was not known to science until 2013. Just last year, researchers from the University of Oxford published a scientific paper in the Journal of Plant Science, indicating that the corona has evolved as a modification of the stamens of the flower.
It is mid-March, and ruderals, Spring’s harbingers, can be seen blooming along the roadsides. Ruderals are plants that inhabit “disturbed ground” such as garden beds, lawns, and roadsides. They live a hardscrabble life on the margin, surviving despite passing feet, lawnmowers, and even herbicides. The most common ruderal (nearly always in bloom) is the dandelion. But there are many others, far less conspicuous.
Just beyond the road’s edge can be seen tiny four-petaled bluish-purple blooms with bright yellow centers. In places a few flower heads that barely rise above the grass while elsewhere, clusters turn the verge almost blue. They are bluets (Houstonia caerulea), natives that are common across most of the United States. They have a vibrant color and delicate form, but no scent or folk use, except for bluet root tea, supposedly used by the Cherokee to treat bedwetting.
Nearby are slender stalks of hoary bittercress (Cardamine hirsuta). A Eurasian winter annual, this hardy immigrant goes by many names, including lamb’s cress, land cress, shotweed, and snapweed. It keeps its leaves close to the ground, sending up wiry stems topped by minute white flowers. How the “bitter” got into its name is not clear, unless it refers to gardeners’ attitudes about it. Although considered a “noxious weed” for taking over lawns and gardens, it is a tasty salad green, slightly peppery in flavor.
A short distance away lies a roadbank that was doused with herbicides late last summer. Already it is covered with new growth: slender green vines with small oval leaves, topped by white flowers. Each flower appears at first glance to have ten petals, but actually has only five, each cleft deeply in two. This Eurasian ruderal may be the world‘s most abundant weed. Sometimes called common chickweed (Stellaria media), it has many other names like starweed, starwort, winterweed, stichwort, and chickwhirtles. It blooms nearly year-round, pollinated by bees and moths. Chickens and small mammals eat the young leaves, while sparrows and finches devour the seeds. Like hairy bittercress, it can be added to salads, and can also be used to treat obesity.
Spring is coming, and the woodland paths will soon be edged with native wildflowers such as round-lobed hepatica (Hepatica americana) and bloodroot (Sanguinaria canadensis). But for now, while the forest rests in the quiet of late winter, the change of seasons can be found instead along Georgia’s roadsides, during this Ruderal Spring.
This article was originally published on March 18, 2010.
As spring slowly approaches, I am finding myself drawn to the ditch at the Hutcheson Ferry end of Piney Woods Church Road. Every visit, I am rewarded by the sighting of another new wildflower to photograph. There is a catch, though: none of the flowers is showy (henbit being perhaps the most dramatic of the bunch, with its flashy, orchid-like blooms), and all of them are minute, with flower heads a few millimeters across. These flowers belong to a group known as the ruderals: wildflowers of waste places (such as roadside ditches). They are nearly all non-natives. Hoary bittercress, for example, hails from Europe, and is common throughout the eastern United States. Of course, unless one is prone to kneeling on the lawn in late winter armed with a magnifying lens, the flower might an unfamiliar one. In this photograph, the blooms are surrounded by long, narrow seed pods, called siliques, which will ripen and then pop open upon being touched, sending a new crop of seeds on their journey. Later in the season, this annual will develop a basal rosette of pinnately lobed leaves; despite “bittercress” in the name, the leaves are edible raw or cooked.
