Little Umbrellas of the Forest Floor

Immature mayapplesMayapple (Podophyllum peltatum) is a common forest floor perennial that flowers in May, but does not actually produce fruit (“apples”) until later in the summer. Recently I was talking to a horticultural professor who was taking his class on a field trip to look for wildflowers. I mentioned to him that the mayapple was about to flower. He shrugged his shoulders and said, “Well, sure, but you can find mayapple anywhere.” Fair enough. Mayapple is apparently the red-eyed vireo of forest wildflowers: it is so abundant that you forget how attractive and interesting it is.

One of the species' many nicknames is “umbrella plant,” which, as it turns out, refers only to the immature, infertile plants. Once established the mayapple spreads via rhizomes. For several years the only thing to emerge above ground is a foot-high stem that attaches to single, deeply lobed leaf. After the leaf is fully-open the plant looks like a parasol emerging from a patio table.

When the plant is mature enough to produce a flower, it sends up a stem that divides into two or three left petioles that support lobate leaves that resemble those on the immature plants, but the petiole is attached at the edge, not the center of the leaf. The flower stem (peduncle) emerges from the divide (axil) between the petioles and supports a single flower bud.

Mayapple flowerMayapple flowers are not dramatically beautiful. The 6 to 9 petals are white and waxy in texture. The stamens and pistil are yellow. The flowers have a pleasant scent and the period of bloom is about three weeks. If the flower is fertilized it produces a two-inch long fruit that contains several seeds. The fruit is edible, but the rest of the plant is poisonous.

P. peltatum is also called “mandrake” or “American mandrake,” but it is not related to the European Mandragora. The latter is a member of the nightshade family (Solanaceae), while Podophyllum is in the barberry family (Berberidaceae). Mandrake plants contain hallucingens like atropine. Mayapple is simply poisonous and produces only nausea and vomiting. Eventually inflammation of the intestinal tract can prove fatal. Even herbalists urge lay people not to experiment with any part of the plant other than the fruit. That said, the chemical constituents of the mayapple inhibit mitotic division of cells, so it has been examined as a possible treatment for cancer (runaway cell division). Etoposide, a semisynthetic derivative of one of the lignans, is currently used in the treatment of small-cell lung cancer and testicular cancer.

Unripe fruitNorth American tribal people apparently used the plant as an emetic and a laxative, to get rid of intestinal worms, warts and moles. The FDA, of course, frowns on all of this, but in the bad old days a decoction of mayapple was sold as a laxative called “Carter's Little Liver Pills.” Modern alternative medicine sources tend to say forget about his plant altogether or only use it topically.

Tribal people and a few 19^th century Americans also ate the fruit (the pulp is yellow when ripe), although it has been variously described as tasteless or syrupy. One maker of mayapple jam in Michigan, however, was quite fond of it and described it as “an exotic tropical aroma. described as mostly guava with hints of papaya and strawberry.” He noted that deer like to eat the ripe fruit and his strategy for gather enough that are ripe is wait until they begin to disappear (harvested by deer, generally toward the end of July) and then to move in and do his own gathering. I must say, though, his recipe includes an enormous amount of sugar.

Back to the Woods

Today (April 29) I took a walk along Taughannock Creek, one of the two main watercourses that pass through or near Trumansburg, where I live. I had noticed on the Google map that a narrow right-of-way extended from the creek, which is part of Taughannock Falls State Park, up to Rabbit Run. For some reason it lined up with the northern border of the fairgrounds, which made it relatively easy to locate. I parked my car on the road and bushwacked down through the bush honeysuckle to the gorge, where I found metal signs indicating the boundary of the park.

Some kind of spleenwortAs I made my way down the steep slope to the water I noticed ferns coming up everywhere in the loose mixture of shale fragments, leaf litter, and soil. I also remembered when this sort of scrambling was much less difficult. This had been how I got much of my exercise in my youth, and there is nothing like to doing the same activity in middle age as you did when you were young to gauge how very much you need to renew and increase the frequency of that activity. So returning to the field is important from both a mental and physical health point of view.

When we moved to Beacon, New York in 1971 my family bought an old Victorian house from an elderly couple. They were apparently downsizing radically and were therefore getting rid of a lot of their belongings. There was a big pile of discarded stuff on the lawn next to the back porch and at the edge of this midden was an old copy of Peterson Field Guide to Birds, an edition from the 1940s, the dust jacket long since lost. It was the discovery of that book at age 10 that started me on the road to becoming a field naturalist.

Soon I was spending the better part of as many days I could manage “in the field.” My interests broadened beyond birds to trees. (I acquired a Golden Guide to Trees.) Then to mammals and the rest of the vertebrates. For some reason I remained focused on these large subjects for the rest of adolescence, not becoming interested in shrubs, wildflowers, or invertebrates until much latter, when other people or coursework introduced these groups to me.

Early saxifrageBut it was being out of doors and paying attention to the identity of things around me that formed the core of my experience. I remember being appalled when my first girlfriend told me that she wasn't really interested in the names of natural objects. For her nature was a mystical experience; she was atttuned to its beauty but focused on forms, textures, colors, and their harmony. We had endless sophomoric arguments about this scientific versus artistic perspective on the natural world.

I did take away an enhanced aesthetic appreciation from this encounter. I did try to back off and to be less analytical, to take a more holistic view. But I did not stop learning the names of species and their habits

Walking in nature and taking it all in has always been a solitary pursuit for me. I never joined a birdwatching or botanical club. I suppose that walking out of doors was very much a meditation, and I have never found a companion who shared this Thoreauvian mixture of science and mysticism.

During the 25 years, while I have been either married or essentially so, I have not very often walked in nature as I did as an adolescent. On the occasions when I tried to share my peculiar passion I have ended up being embarrassed: I have never been uninterested in getting exercise or reaching a particular destination (“hiking”) nor felt particularly upset when I haven't been able to identify something (“field trip”).

As I scrambled down the slope of Taughannock Creek I was curious as to what species these ferns were, but I hadn't brought any sort of field guide with me. In late April ferns were coming up everywhere. The only ones I had a prayer of identifying were the spleenworts, which are relatively small ferns that tend to grow on rock outgrops. They are calciphiles, and the local bedrock has calcium carbonate in the cement that binds it together. I didn't know what they were below the genus level though.

Closer to the water there were also white wildflowers emerging everywhere from the outcrops. They looked vaguely familiar but I couldn't place them. I enumerated characteristics. Five petaled flowers about a centimeter across growing on branching stalks that were almost succulent and finely haired. These stalks lacked any leaves, but sprang from a basal rosette that consisted of oval, slightly flesh leaves with blunt teeth.

Virginia bluebellsWhen I returned home I cast about on the Internet (I don't have a wildflower guide anymore) without much luck until I decided to simply type all the descriptive words into the browser.

They turned out to be saxifrages. A little more digging revealed them to be early saxifrage (Saxifraga virginensis), not uncommon in the least, but I had only seen cultivated saxifrage before. They were growing exactly where they usually grow: on outcrops along streams.

I emerged from the gorge and reached a wetland area in an old oxbox that stretched away from the current creek course and was filled with what turned out to be Virginia bluebells (Mertensia virginica).

Again I took stock of salient characters, commited them to memory, and looked them up by the same method as the saxifrage. Pendant funnel-shaped (“salverform”) pale blue flowers dangling in loose bunches (“cymes”) from plants that appeared semi-succulent. The oval leaves held upright making an acute angle with the stem.

I had never seen either of these plants in flower before in 41 years of walking out of doors. This is perhaps because I haven't don't it enough in the last 25 and therefore haven't spent enough time in the field in central New York. That is about to change.



Trees at Their Limit

It has been a bizarre late winter and spring, with flowers and leaves budding and opening four to six weeks ahead of their average dates. There is always variation from year to year, and it was interesting that the media announced that March was the fourth warmest on record. While that is pretty warm, it is noteworthy that there are three other years that experienced even warmer temperatures. One media report noted that the three warmer years were in 1992, 1999, and 2000. Because they were all in the recent past that connotes a trend. If they are scattered through the entire length of the record, then there it would suggest a recurring phenomenon. This is where weather observation meets climate study.

Magnolia stellataBiota respond to warming trends by changing their geographical distributions, which takes less time than evolving to adapt to changing physical environmental conditions. Looking at the maps of the geographic distributions of many warm weather plants and animals reveals disjunct populations around a larger central coherent range. When I lived in the Hudson Valley as a teenager in the 1970s I was intrigued by eastern fence lizards that lived on the south-facing slopes of the Hudson Highlands and the prickly pear cactus that grew along the railroad tracks by the river and apparently in arid settings up the in the hills. I never saw those, but read about them and saw on the USGS topographic map that there was a Prickly Pear Hill outside of Peekskill. The lizard populations were separated from each other by a few miles and from the northern edge of the main body of the population in New Jersey by about a hundred miles. The cactus was found in scattered locations along the coast but there were no other inland populations.

This spring the warm temperatures caused the magnolias in the Ithaca area to bloom in third week of March when temperatures peaked in the low 80s Fahrenheit. In the fourth week of March the temperatures plunges to between 15 and 20 degrees at night and remained in the 30s during the day. The fleshy pink and white flowers of the saucer magnolias (Magnolia x soulangeana) turned brown and shriveled, but the star magnolias (Magnolia stellata) seemed to come through the freeze without withering.

Magnolia x soulangeanaThe saucer magnolia is a hydrid of M. liliformis and M. denudata. M. liliformis is a native of the Yunnan and Sichuan provinces of mountainous southwest China. (M. denudata is native to southern China and hardy north to about St. Louis in the U.S.) M. liliformis is hardy to Zone 6 in the United States, which extends up from Pennsylvania through the central Finger Lakes to the Ontario lake plain and then wraps westward down into Ohio.

This is, incidentally, also the northern extent of the range of M. acuminata, the cucumber tree, one of the eight magnolia species native to the United States. The main range of the cucumber tree is centered on the Applachian Mountains with disjunct patch of occurrence scattered over a much wider region all around. This resembles the ranges of fence lizard, prickly pear cactus (and also the ranges of many salamanders, rhododendrons and other taxa).

This phenomenon of warm-adapted plants and animals having disjunct “relict” populations isolated in mesoclimates where conditions that they can cope with still exist is likely the historical legacy of the “hypsithermal” or “Holocene climatic optimum.” This warm period is acknowledged to be caused by a peak in solar radiation associated with a maximum in the tilt angle of the Earth's axis (24 degrees off the perpendicular to the plane of orbit or ecliptic). It ended roughly four thousand years ago after persisting for three to four thousand years.

Magnolia acuminataA single specimen of M. acuminata is known to be growing in Smith Woods, a 30-acre modified “old growth” plot at the edge of Trumansburg, N.Y., north of Ithaca. Descriptions of the plant note that it often grows singly rather than in stands. Smith Woods is also home to a population of swamp white oak (Quercus bicolor), which has a range in New York State almost identical to the cucumber tree, extending eastward along Lake Ontario and then south through the centeral Finger Lakes.

M. acuminata, M. stellata, M. liliformis, and M. denudata are all members of the subgenus and section of Magnolia called Yulania. They all seem adapted (whether native to China or North America) to temperate inland climates with seasonal temperature variations (all are deciduous).

In contrast, the symbol of the south, M. grandiflora or bull bay, and its smaller relative M. virginiana or sweetbay, are members of the root group of Magnolia, the subgenus and section Magnolia. These plants are associated with warm temperate coastal climates. M. grandiflora's natural range extends only north to North Carolina, where like other taxa mentioned above, it has disjunct coastal populations cut off from the rest of the distribution. Sweetbay is found along the coast up to northern New Jersey, with a disjunct population on the southern shore of Long Island.

I am not aware of anyone trying to grow M. grandiflora or even M. viriginiana in the central Finger Lakes region and it interesting that the Yulania species and their derivate cultivars seem right at the edge of their tolerance with the native M. acuminata persisting in small numbers and M. stellata coming through a hard frost better than M. x soulangeana, which seem to be limited by the contribution of M. denudata, which ranges from central to eastern China, a more moderate climate than most of the native range of M. liliformis. M. x soulangeana was developed in 1820 outside Paris, by French plantsman Étienne Soulange-Bodin, a retired cavalry officer, at his château de Fromont, a climate moderated by the Gulf Stream.

The magnolias blooms before they leaf out. If frost kills the blossoms, it prevents pollination and seed production for that year. If this happens irregularly, then it would little effect on the persistence of a population. If it begins to happen regularly, then over time the failure to produce new generation would cause the species to disappear locall, which is presumably what happen in the areas between the main range of these magnolia species and their disjunct populations.

Pronouncing Forsythia

When I was growing up on Spy Hill in Beacon, New York, our neighbor was a widower in his 70s who came over to our house for dinner every Wednesday for several years. H. Mortimer Brockway was the last of his family to run the Brockway brickyard.

Ruins of the Brockway brickworksThrough the 19^th century the family had done well; they had made a lot of bricks and shipped them down the Hudson. But by the time Mr. Brockway was in college – he went to Harvard – the business was entering a crisis stage: they were running out of clay.

The Brockways went so far as to tear down their family home in order to get to the last clay deposit underneath it. Several of the elaborately ornamental pieces of furniture in his home down the hill from ours were far too big for the rooms. They were family heirlooms; the last remnants of the Brockway fortune.

Mr. Brockway owned several acres on the northwest flank of Spy Hill and much of his land was planted in flowering shrubs and trees and perennials. His aunt had been a florist and he was the only male member of the Tioronda Garden Club.

As role models went, he was an esoteric one. When I went out into the world and learned a bit more about social history I realized that his beliefs, perspective, and body of knowledge represented a sort of an Edwardian time capsule. He repeated without irony many of the pseudo-science theories of the turn of the 20^th century, including the idea that any trace of advanced civilization in the Mediterranean must have come from Northern (insert the word “Aryan” at will anywhere here) invaders who were assimilated into the population.

It seemed as though it had been several decades since anyone at all had challenged him on any piece of knowledge (or opinion) that he let fly. And on his weekly visits to help us eat our pasta and red sauce dinner he seemed a bit non-plussed when my mother (it was always my mother) challenged him on the pronounciation of various words. She didn't challenge him on his “body of knowledge,” although I assume she had her suspicions.

But she did have confidence in her ability to pronounce the English language. He, for example, insisted on pronouncing “innovative” as “in-NO-vah-tive,” while my mother rather held to “IN-no-vae-tive.” The dictionary would come out and a score would be settled. Not satisfied with merely being correct, my mother actually kept a list of the words they jousted over written down on a small piece of note paper and pinned to the inside of the pantry door.

Forsythia flowersOne evening Mr. Brockway's horticultural knowledge collided with his arcane sense of pronounciation. It was likely the early spring, late March or early April, when the Forsythia was in bloom in everybody's yard. When he brought up the beauty of a particular row – perhaps the one along Rombout Avenue in front of his house – he said “for-SY-thia” with the second vowel pronounced as a long 'I'. My mother had never heard anyone say the name of this common shrub like this before. “It's was named for a man called 'Forsyth,'” insisted Mr. Brockway, “so it must be pronounced 'for-SY-thia' because that is how you would say his name.”

As it turned out, this time he was correct on both counts. Although the most common pronounciation is with a short 'I' sound in the second syllable, the long 'I' is given as an alternative (and one guesses, older) way of referring to this ubiquitous member of the olive family.

William Forsyth was an 18^th century Scottish horticulturist (he died in 1804) who was one of the founders of the Royal Horticultural Society. In 1779 he was appointed as chief superintendent of the royal gardens at Kensington and St James’s. He would have been at that post when Carl Peter Thunberg, a pupil of Karl Linné (Linneaus), first saw a yellow-flowering shrub in a Japanese garden in the 1780s and listed it, Forsythia suspensa, in his Flora Japonica in 1784. It is native to central and eastern China. The large (to 10 feet tall) shrub has a weeping habit and is one of the species that was eventually crossed to create the Forsythia x intermedia hybrid that is usually seen in designed landscapes.

Forsythia X intermedia LynwoodIn the 1840s the Scottish merchant and horticulturalist Robert Fortune noticed a different species of Forsythia in a Chinese garden. The species F. viridissma was introduced to Europe and became a popular addition to designed landscapes. It was crossed with F. suspensa to produce x intermedia.

Through the rest of the 19^th century several more species were identified in China, Japan, and Korea (and, oddly enough, one in the Balkans). Although many of them have been used to create cultivars, the intermedia hydrid is still standard.

Mr. Brockway grew tree peonies, 'regular' peonies, gladiolas , dahlias, ancient varieties of pear, and a host of other classical plants. It was only years later, when I was visiting designed landscapes from the early 20^th century on a regular basis, that I realized that I'd grown up next to the remnant of one of these Edwardian creations. Mr. Brockway was a fit and active septugenarian, but he could take care of everything that had been planted on his property over the years. He dutifully dup up his gladiolas ever fall and put them in the basement, but he didn't trim his forsythia bushes very often, and he never called them by their common name … golden bells.



Put Your Palms Together

Palms grow throughout the tropics and in much of the subtropics, a few of them ranging up into temperate latitudes in both the northern and southern hemispheres. The genus Homo evolved in the tropics and developed agriculture there, building civilizations in the subtropics where not everyone was a farmer. Urban centers developed where people bought their food instead of growing it. So food became a commodity, something to be transported from the place where it was grown and harvested to the place where it was consumed. 

Palms are ubiquitous, growing in rainforests and deserts, in mountains and on the beach. There are approximately 2,600 species around the world, displaying an impressive amount of diversity. It is therefore not surprising that many species have been turned into resources.

Cocoanuts are the fruit of Cocos nucifera. But this is not just about eating cocoanuts. According James Duke of the horticulture department at Purdue University, “At any one time a coconut palm has 12 different crops of nuts on it, from opening flower to ripe nut.” They go on to describe the various ways that the flowers, buds, and nuts in various stages of ripeness can be transformed into something edible.

Oil palm plantationIt isn't all about food either. “[The] nut has a husk, which is a mass of packed fibers called coir," Duke wrote, "which can be woven into strong twine or rope, and is used for padding mattresses, upholstery and life-preservers. Fiber resistant to sea water and is used for cables and rigging on ships, for making mats, rugs, bags, brooms, brushes, and olive oil filters in Italy and Greece ...”

Coconut oil is derived from the kernel of C. nucifera and palm oil is extracted from the fruit of Elaeis guineensis, the “oil palm.” These tropical oils made their way out of Africa and South America during the late colonial period. Non comestible uses for palm oil included machine lubrication and soap making (“That's Palmolive you're soaking in!”). Of course in the usual pattern of increasing demand caused by more and greater uses further afield from the point of origin, oil palm growing has expanded and is expanding at a rate that alarms environmentalists. Tropical forests are cut down and replaced with ecologically sterile palm plantations throughout the low latitudes.

Palm oil is highly saturated, which slows its oxidation, a desirable quality in the production of deep-fried and processed foods. It is also realtively cheap, another plus. Unfortunately saturated fats lead to the accumulation of both low-density and high-density cholesterols in human circulatory systems, promoting heart disease.

Rattan palmThe image of the palm tree is iconic: the tall limb-less truck with the thatchy mop of large leaves sprouting out of the top. But, in fact, palms (the family Arenaceae) have several growth habits. The diametrical opposite of the tree-like icon is the climbing palm. The vine-like plants grow on other plants. The rattans are a diverse tribe (Calameae) of climbers that is native to southeast Asia and widely cultivated there. Rattan furniture became fashionable in the Victorian Era and has remained so to this day.

While tropical forest is cleared for oil palm plantations, rattan is grown commercially within the existing forest. While this is an inherently sustainable practice, rattan growers still manage to over-harvest their crop in some places and injure the condition of the “host forest” in others.

Rattan produces poles that are similar to bamboo, but solid rather than hollow. The outer layer is thorny and must be removed before use. The second layer can be stripped off to create cane, which is then woven to make the matting that is strung between the structural framework built from the poles. Rattan is often lumped under the general rubric of "wicker," which encompasses all woven plant materials including those made from grasses, rushes and willow (the original wicker material).

Flag of South CarolinaPalms are also grown commercially and used in both private and public designed landscapes to create a classic tropical look. The strong idenfication of palms with the exotic tropics has led to palms being planted well outside their natural ranges with the Isles of Scilly off the southwest coast of England being perhaps one of the more famous, although they are also part of estate landscapes in Ireland as well. In both places the benevolent effects of the Gulf Stream allow the palms to live well north of their natural range.

In the southeastern United States the natural range of palmetto palms extends as far north as North Carolina. The silhouette of the saw palmetto is the symbol of the state of South Carolina. While most palms have pinnate leaves with leaflet attached to long central axes, it is the palmate leaved species (like the palmettos) that give the family its name. Palmate leaves lack the central axis and the leaves radiate outward like finger from a central region.

The leaves' resemblance to the palm of a hand are what give the trees their name. The Romans called that part of the hand palma and gave the trees the same name.