In my Eureka Nature column, August 16, 2012, in the Eureka Springs Independent Newspaper, I posed the question what’s in the name Leatherwood (as in Lake Leatherwood and Leatherwood Creek) and whether that name referred to a small shrub known as Leatherwood (Dirca palustris) or some other plant, person, or place. The plant had not been collected in Carroll County since the early 20th century. In fact it is absent for Carroll County in the new Atlas of the Vascular Plants of Arkansas a publication of the Arkansas Vascular Flora Project, just released a few weeks ago. The Atlas has county range maps for 2,892 species of vascular plants known from Arkansas. Of course, it reflects what we don’t know as much as what we do know. It presents the opportunity to fill gaps in knowledge. Trained field botanists working in Arkansas are an extremely rare species. There’s simply not legions of botanists doing systematic field botany and collecting herbarium specimens— dried, pressed, physical specimens — the scientific foundation for plant geography and taxonomy.
On Sunday May 4th, I was delighted to be invited to tag along with a small legion of botanists at Lake Leatherwood. Led by Theo Whitsel, long-time botanist with the Arkansas Natural Heritage Commission, a group of 12 “brain trust” leading botanical experts from Arkansas and Missouri, did a quick walk through Leatherwood trails just to see what might be there. It was a quick “drive-by” on their way to other locations such as the new Devil’s Eyebrow Natural Area in Benton County, just north of Eureka Springs off of Highway 62, a 2,000 acre research just dedicated a year ago on the cold, snowy morning of May 3rd 2013.
To my surprise, there along the edge of the Hyde Hollow drainage growing in the moist gravel at the edge of the creek was Dirca palustris, the Leatherwood shrub. I had been in that same location many times before, but just hadn’t noticed it. It’s non-showy flowers are among the earliest of the season, blooming long before the leaves unfold.
Leatherwood is a small shrub, about three feet tall; a member of the mezerum family (Thymelaeaceae) found along creek bottoms from New Brunswick, west to North Dakota, couth to Florida and Louisiana. It is found in northwest and southwest Arkansas, but is not particularly common anywhere. Dirca is the only North American genus of the largely tropical plant family to which it belongs. Dirca palustris is an obscure medicinal plant, which like other members of the mezerum family are better known for their toxicity than their medicinal benefits. The fruit is considered toxic, and the fresh root, applied to the skin causes blistering. Tiny doses of the fresh bark causes vomiting and diarrhea. It is among the most obscure American medicinal plants.
Naturalist-explorer C.S. Rafinesque (1783-1840) provides insights into the potential of Leatherwood in Medical flora, or Manual of the medical botany of the United States of North America. 2 vols. Philadelphia, Samuel C. Atkinson. In the first volume (pp: 158-161) he notes:
“The blossoms are scentless and appear very early in the Spring, as soon as the Maples blossoms, long before the leaves are unfolded. The bark is very tough, can hardly be broken, and tearing in long stripes is used as yet in many parts for ropes, a practice borrowed from the Indian tribes : the wood is also flexible. The berries are poisonous, children must avoid them : if eaten by mistake, an emetic must be resorted to. . . . When the bark is chewed it produces salivation, it is so tough that it cannot be reduced to powder, but forms only a kind of lint. The watery preparations are nearly inert.”
In another interesting twist to the Leatherwood, story is the work of the Kansas State University research team of Aaron J. Floden, Mark H. Mayfield and Carolyn J. Ferguson in 2009. A new, single population of “Dirca palustris” was collected in Kansas in 1997. As the researchers looked more closely at the plant, they discovered it was quite distinct from D. palustris, in fact in 2009 they named a new previously undescribed species—Dirca decipiens (meaning “deceptive”). Subsequently they conducted simultaneous surveys of flowering Leatherwood plants in Kansas, Missouri, and Arkansas. These field observations resulted in finding the newly named Dirca decipiens in both Benton and Carroll counties in Arkansas. It differs in producing larger fruits, without stalks, and hairy branchlets, among other features. In 2009, this rare plant was only known from three populations. Another major caveat is that it occurs on northeast facing bluffs and slopes above the valley floor in rather dry limestone habitats, rather than along creeks in rich wooded bottomlands, where one finds Dirca palustris. Dirca decipiens blooms about a week later, too (Florden, A.J., M.H. Mayfield, and C. J. Ferguson. A new narrowly endemic species of Dirca (Thymelaeaceae) from Kansas and Arkansas, with a phylogenetic overview and taxonomic synopsis of the genus” J. Bot. Res. Inst. Texas 3(2):485–499, 2009.
To my mind the mystery of where the name Leatherwood originated relative to the lake, park, and creeks of the same name is solved. No more speculation. Case closed.
Adapted and expanded from Steven Foster’s Eureka Nature column, Eureka Springs Independent Newspaper, August 16 2012 & May 7, 2014
In honor of Jim Duke’s 85th birthday (April 4th, 2014), and the release of the 3rd edition of our Peterson Field Guide to Medicinal Plants: Eastern and Central North America (release date: April 8th, 2014). A personality profile first published in Otober 2001, updated April 4, 2014,
Jim Duke leaned over to me and warned in his Alabama drawl, “You’re going to get the tropical bug.”
My forehead stiffened with a worried glance. I pulled out my immunization card. ”What do you mean? I’ve got all of my shots. And here’s my malaria pills.”
“No,” Duke comforted, “I mean, after you come here once, you will want to come back as much as you can. If it wasn’t for the fact, that I can’t get Peggy [Jim’s wife] to live down here, I would move here myself.”
We were on a flight from Miami to the humid, heat-laden air of the ancient rainforest city of Iquitos, Peru. You may remember the main character in the 1993 new age mystery novel TheCelestine Prophecy “driving” to Iquitos. The fact is, there’s only two ways to get there — by air or via the Amazon River. There are no roads to Iquitos. “capital of the Amazon.” I was traveling to the Amazon for the first time with the American Botanical Council’s “Pharmacy from the Rainforest” program in the fall of 1995. Since our group numbered over 100 people, the instructors got bumped-up to first class. I sat next to Jim Duke, who had made the trip too many times to count (up to ten times a year). It was my first trip to the real tropics, besides a short stint in Guatemala during the dry season. The flight was rough. The flight attendants plied us with drinks, and our conversation lasted the length of the flight. Duke treated me like he was leading a kid to a candy store.
On the four-hour flight, he told me story after story, and prepared me for what lie ahead. “Every ten feet you walk, you will see something different,” Jim explained. “The diversity is incredible. Near my home in Maryland there are about 30 species of woody plants per hectare. In the Peruvian rainforest there are over 300 woody species per hectare. This unbelievable diversity must be must be experienced to be believed. Words can’t describe it.”
After a night in Iquitos, the 120+ participants loaded into boats and went down the Amazon River to Explorama Lodge, a rustic, but comfortable facility featuring all the creature comforts a rainforest camp can offer (with emphasis on “creature” as a tarantula-sized spider crawled across my room). “You get it out,” I told my roommate Larry Wilson, the herpetologist on the trip. You’re the animal guy. I’m just a plant guy.” He grudgingly obliged. Explorama Lodge served as the main camp for the trip. Two other locales were featured, Napo Camp, and ACEER Camp, up a major Amazon tributary—the Napo River.
Dr. Duke was the perfect host. One afternoon he took herbalist Amanda McQuade and me to visit a friend of his who lived on the Amazon’s banks. The farmer grew sugar cane, which he turned into a sickly sweet version of white lightening in a battered old copper still. “Rum”, Jim called it. The farmer’s wife made drinks for us — half fresh-squeezed ginger juice and half “rum”. It sure took the cares away, and cured the tourista, too. Why, if an Anaconda had swam by in the nearby rushing waters of the Amazon, I might have just hopped on its back and taken a ride to our next day’s venue — ACEER.
ACEER— the Amazon Center for Environmental Education and Research— was a couple hours away by boat (followed by a 30-minute hike through the primary rainforest. ACEER is Jim Duke’s home away from home, now that he is “retired”. At ACEER, Jim Duke, along his local shaman colleague, Don Antonio, freely share knowledge on the ethnobotany of Amazonia. Duke’s infectious love of the Amazon, its people and flora inspire all who travel there, as he tromps barefoot through the jungle, seemingly oblivious to the ants, swarms of insects, and occasional reptile that might lurk beneath the understory. For those who know Jim Duke from North American venues such as scientific conferences, herb gatherings, or a North Carolina bluegrass stage, you know that his is really at home — where his heart is — when you see him in the primary rainforest of the Amazon.
Duke was right about his prediction. I did get the tropical bug. Since traveling to the Amazon with him, I am committed to taking a trip to a tropical location at least once a year. I thank him for that.
I met Jim Duke in the autumn of 1978 long before his fame had traveled from the halls of relative academic obscurity to herbal celebrity. We met in the backyard of Paul Lee PhD who had been unceremoniously dismissed from a teaching position at Harvard (along with Timothy Leary and Richard Alpert aka Ram Dass) after publication in the Harvard Crimson of an exposé on LSD experimentation co-authored by an undergraduate student later to become guru of alternative medicine—Andrew Weil, M.D.
Jim had just walked to Paul’s house from his hotel, with notebook in hand, documenting varieties of opium poppies (Papaversomniferum) whichgrew as ornamentals in people’s yards. At the time I was 21 years old. I had just left the Sabbathday Lake Maine Shaker Community where I had been for four years. Having grown up in Maine, that trip to California, was my first trip west — west of New York City. Here, I was meeting some of the giants of medicinal plant research for the first time. We were attending an international herb symposium at U.C. Santa Cruz organized by Paul Lee.
First impressions are everything. I didn’t even know how to start a conversation with someone of the stature of Jim Duke. He was one of the few medicinal plants researchers at the time, and certainly the only scientist in the Federal government researching herbal medicines (at least clandestinely if not officially). At the time he was Chief of USDA’s Economic Botany Laboratory in the Agricultural Research Service in Beltsville, Maryland.
Humility rarely follows success. Duke, as he refers to himself, turned out to be a Southern gentleman first, a famous scientist second. His interest in poppies grew out of his second stint with USDA starting in 1971, which took him to Iran to study species diversity in opium poppies as part of his professional role in researching crop diversification and medicinal plants in developing counties. His passion for how humans use plants as medicine, rolled from his tongue like a kid licking a lollypop. At once, he put me at ease. Here was a man who was more interested in what I might have to say to him than in what he might have to say to me. He stood next to a Mullein plant in Paul Lee’s garden. I snapped a photograph as Jim Duke recited a poem.
The photo of him I took that day along with the poem on mullein, are in one of Duke’s more obscure of over thirty books, Herbalbum-An Anthology of Varicose Verse, published in a staple-bound photocopied edition in 1985 — a collection of over 400 herbal poems and a couple dozen songs set to bluegrass melodies. In case you are wondering how the syllables breakout for pronunciation, that’s “herbal-bum” for the poems. The songs were released under the same Herbalbum title, but in this case pronounced “herb-album”— a vinyl record of bluegrass songs written and performed by Jim Duke and his bluegrass buddies (later released on tape and CD).
Dr. James A Duke, a key figure of the “herbal renaissance,” a phrase coined by Paul Lee, is a renaissance man in the broadest sense. Born in Birmingham, Alabama, April 4, 1929, Jim Duke was a bluegrass fiddler by age 16, even appearing at the Grande Ole Opry. An interest in plants was not far behind his interest in music. In 1955 he took a degree in botany from the University of North Carolina. In 1961 the same institution conferred a doctorate in botany upon him. Postgraduate work took him to Washington University and Missouri Botanical Garden in St. Louis. It was there where he developed what has become to this day, as he puts it, “my overriding interest — neotropical ethnobotany.”
Early in Duke’s career with Missouri Botanical Garden his work took him to Panama where he penned painstaking technical descriptions of plants in eleven plants families for the Flora of Panama project, published in the Annals of the Missouri Botanical Garden. During his years in Panama he also studied the ethnobotany of the Choco and Cuna native groups. The Choco are a forest people who lived scattered along rivers. The Cuna live in villages. Another fruit of these years was his first book — Isthmanian Ethnobotanical Dictionary, a 96-page handbook describing medicinal plants of the Central American isthmus.
In 1963, Jim Duke took a position with the USDA in Beltsville, Maryland, focusing on tropical ecology, especially seedling ecology. From 1965 to 1971, he worked on ecological and ethnological research in Panama and Colombia for Battelle Columbus Laboratories. Jim Duke doesn’t talk much about this work. However, if you put some of the pieces of the puzzle together, his more obscure scientific publications of this era reveal the focus research.
Many of his publications were prepared for his employer on behalf of the former Atomic Energy Commission. The work was akin to environmental impact statements on the effects of radiation on tropical organisms. President Kennedy had an idea. He initiated a feasibility study to widen the Panama Canal, or perhaps excavate a new canal to accommodate supertankers. The project was called the Atlantic-Pacific Interoceanic Canal. America had a tool that would easily accomplish the excavation work —nuclear devices— nuke the Central American isthmus to create a new canal from the Atlantic to the Pacific! Duke’s studies may have helped to show that the excavation technique may not be such a good idea.
After that stint, Duke returned to USDA in 1971 where he worked on crop diversification, creating a database called the “Crop Diversification Matrix” with extensive biological, ecological and economic data on thousands of cultivated crops. His interest in medicinal plants never waned no matter what unrelated tasks government bureaucrats pushed his way. In 1977 he became Chief of the Medicinal Plant Laboratory at USDA’s Agricultural Research Service in Beltsville, Maryland, and then Chief of USDA’s Economic Botany Laboratory. At the time, USDA was under contract with the National Cancer Institute (NCI) to collect plant materials from all over the world for screening for anti-cancer activity.
One NCI scientist with a vision to explore the plant world for potential anti-cancer compounds was the late Dr. Jonathan L. Hartwell (1906-1991). His pioneering work on the common mayapple (Podophyllum peltatum) resulted in the isolation of podophyllotoxin and several other compounds known as lignans, which eventually led to the development of drugs used in chemotherapy for the treatment of testicular cancer and small cell lung cancer. In July 1960, a contract was established with NCI for USDA to begin collections of plant materials for screening potential new anticancer compounds. Over the next twenty-years, about 35,000 species of higher (flowering) plants were screened for activity against cancer. About 3,000 of those demonstrated reproducible activity. A small fraction of these (including mayapple and yew derivatives) were eventually chosen for clinical trials. Jim Duke supervised these collections in the later years of the program.
On October 2, 1981, the Board of Scientific Counselors, Division of Cancer Treatment at NCI decided to abolish its plant-screening program — not enough new drugs came from the research. Later in the 1980s new automated laboratory technologies emerged, with better cell lines targeted toward human cancers resulting in the NCI reforming its natural products screening program. This time, however, collection contracts were given to major botanical institutions such as Missouri Botanical Garden and the New York Botanical Garden, rather than USDA.
Jim Duke continued his work at USDA as Chief of the Germplasm Resources Laboratory, collecting data and plant material on food crops from around the world. He continued his association with the National Institutes of Health and the NCI working on potential anti-cancer and anti-AIDs drug leads. Later, from 1990-1992, he consulted with NCI’s Designer Food Program (to document plants with potential cancer-preventing activity) under the direction of the late Dr. Herb Pierson. During the Reagan Administration, he was also charged with the unenviable, and as Jim Duke himself admits, “impossible” task of finding a replacement crop in the Andes for coca, the ancient Inca stimulant and source of its abused alkaloid, cocaine.
Duke not only continued his personal interest in medicinal plants — increasing his database to include over 80,000 plant species — but began a flurry of publication activity which continues unabashed. Works from this era include many of his important scholarly books such as the CRC Handbook of Medicinal Herbs, (CRC Press 1985), a standard technical reference, yet still a good read for the layperson.
After more than 30 years of service, Dr. Duke retired from USDA in September of 1995. “Retirement” is hardly a word that applies in the traditional sense. It was more like a coming out party. What retirement meant for the herb world was that Jim Duke could write what he wanted to write and say what he wanted to say—no more government sensors. Retirement for him, by fate not design, was the beginning of a new career as America’s herbal guru, tempered by a dose of Alabama charm.
Ten years ago Dr. Duke lecture circuit included about 100 venues a and he led nearly 100 trips to the Amazon. He now spends most of his time at his rural farm in Maryland — Herbal Vineyard — with wife of many decades, Peggy Duke, a noted botanical illustrator and teacher in her own right. There you will find “the barefoot doctor” pulling weeds in his vast organic herb garden, perhaps the largest private medicinal herb garden in the country, with over 80 plots of plants arranged by disease condition, representing hundreds of species of medicinal herbs.
Many of the databases he produced during his decades as USDA, such as Father Nature’s Farmacy, are available on-line at (http://www.ars-grin.gov/duke/). There, you will find a wealth of information on the phytochemistry, ethnobotany, and biological activities of thousands of medicinal plants.
How do you write a story about someone you’ve known for 23 years [now for 36 years] who’s been profiled by everyone from People Magazine to the New York Times (and more than once in each) without sounding glib? When I started writing this profile, I decided to go through my Duke files. That search netted a pile of correspondence, articles by him or about nearly two feet tall. Sometimes having too much is worse than having too little!
At a seemingly ageless 85 years young , Jim Duke is still in producing new books. My library is arranged by subject; except for two authors — famed nineteenth century Cincinnati pharmacist, John Uri Lloyd and Dr. James A. Duke — both the only authors in the medicinal plant field prolific enough to warrant their own shelves. Duke has some catching up to do, though. My shelf of John Uri Lloyd books is three feet wide. My shelf of Jim Duke books is a mere two feet wide. I expect Jim Duke will make up the difference, and I hope one of the titles that fills that space will be a Jim Duke memoir [hasn’t happened yet].
The Duke Lexicon up to 2001
Duke, J. A. 1972. Isthmanian Ethnobotanical Dictionary. Fulton, Maryland: Author.
Duke, J. A. 1972. Lewd Latin Lexicon. Fulton, Maryland: Author. [A dictionary of colloquial slang in various Central American languages and dialects]
Duke, J. A. 1981. Handbook of Legumes of World Economic Importance. New York: Plenum Press.
Duke, J. A. 1981. Medicinal Plants of the Bible. Buffalo, New York: Trado-Medic Books.
Duke, J. A. 1985. Culinary Herbs: A Potpourri. New York: Conch Magazine, Ltd., Publishers.
Duke, J. A. and E. S. Ayensu 1985. Medicinal Plants of China. Algonac, Michigan, Reference Publications, Inc.
Duke, J. A. 1985. CRC Handbook of Medicinal Herbs. Boca Raton, Florida, CRC Press, Inc.
Duke, J. A. 1985. Herbalbum: An Anthology of Varicose Verse. Fulton, Maryland: Author.
Duke, J. A. 1986. Handbook of Northeastern Indian Medicinal Plants. Lincoln, Massachusetts, Quarterman Publications, Inc.
Duke, J. A. and A. A. Atchley 1986. CRC Handbook of Proximate Analysis Tables of Higher Plants. Boca Raton, Florida, CRC Press, Inc.
I think it’s great that the Eureka Springs City Council is proposing Ordinance No. 2201, which aims to “update and expand City beautification and to eliminate health and safety issues.” Citizens asked the Council to update the current code so as to “keep privately owned areas clean and safe. . . .” Good idea?
The proposed ordinance includes item “A” of Section 1, which involves my specialty “plant vegetation.” When human nature is compelled to legislate Mother Nature, I think God puts his hands on his hips, raises an eyebrow, frowns and shakes his head in disbelief. “How am I going to explain this to Mother Nature?” God muses. “She’s not going to like it.”
The ordinance contains well-meaning and ambitiously ambiguous definitions of broad categories of vegetation that grow where you live (property ownership not required!)—“owner(s) or occupants(s) of property” within Eureka Springs will be required to “maintain, cut, and/or remove weeds, grass and/or any other non-cultivated plant(s) (flowers, shrubs, vegetable plants etc.), which exceed the height of eight (8) inches. Bamboo may be cultivated with in the city limits, but should not encroach upon another citizens/city property or become an obstacle to vision while driving.”
I have to cut “any non-cultivated plants to a height under 8 inches?” Is the Council aware that trees are plants? I am thoroughly confused about the bamboo provision. Bamboo is a grass—a member of the Graminae or Poaceae—the very clearly defined grass family. But grasses are already covered elsewhere in the ordinance. Does the bamboo provision in the absence of a definition pertain to plants to which the common name “bamboo” is applied, such as Nandina domestica, commonly grown in Eureka Springs and known as “heavenly bamboo”? It’s not technically a bamboo therefore not a grass; it’s just called “heavenly bamboo.” Maybe the Council really meant hellish bamboo for purposes of the ordinance. Heavenly bamboo like hellish bamboo is an “obstacle to vision while driving.” What’s with the blatant discrimination against bamboo as “an obstacle to vision?” What about all of the other plants that are obstacles to vision while driving?
In the Building Inspector’s job description, I ask is he or she qualified or competent to distinguish grass from bamboo, heavenly bamboo from hellish bamboo, non-cultivated plants from cultivated plants, weeds from weed?
Thank you City Council for providing my comedic introduction for a summer lecture tour on how humans relate to plants.
You can find the draft of the proposed ordinance at the official City of Eureka Springs website. Just click on the “Ordinances” menu tab, then click on “Proposed Ordinances.” Whoops—that link doesn’t work — “sorry for any inconvenience.” Seems like updating the website has gone the way of updating the street sweeper.
As Mother Nature said to God, “You created this human problem. Please fix it.”
The brilliant golden yellow leaves of the Ginkgo trees flanking the back entrance of our local post office, once they are ready to fall, will drop in a few hours time, raining from the thick branches like small fans twirling from the sky. After our first hard killing freeze last night, the Ginkgo leaves fell today.
The shriveling fruits, which look like half-sized wild persimmons, may persist for a few days after the leaves, then fall to the ground. Fruits are always a tempting curiosity. In fact, you can buy Ginkgo seeds as a food item in Chinese markets, but these have been prepared and processed to render them safe to eat. You should not be tempted to pick-up the freshly fallen fruits, which will cause contact dermatitis similar to the rash produced by poison ivy. The fruits have a fragrance that has been described as a blend between baby vomit and what a dog might leave on a sidewalk. That should be enough to entice you to leave them be.
I suspect that these trees were planted about the time the Eureka Springs Post Office building was completed in 1918, rather than in 1973 when the building was expanded and the service parking lot in the back was developed. The trees are of a fairly good size, plus for many decades most ginkgo trees available from nurseries in the United States have represented male branches grafted on to rootstocks. Within forty years after Ginkgos were widely planted as a street tree by the mid 1800s, female trees like those at Eureka Spring’s Post Office began to leave their bad smelling fruits on sidewalks. Female Ginkgos are simply not a neat and tidy street tree. Notwithstanding the beauty of the fall foliage, the fact that these two trees are females makes them a unique and interesting part of Eureka Springs’ heritage.
Ginkgo was common 175 to 200 million years ago, when dinosaurs roamed the earth. This primitive tree is considered the oldest living tree species on earth. Ginkgo is monotypic. That is, in the ginkgo family there is only one species in one genus — the only surviving member of the ancient and primitive ginkgo family—Ginkgoaceae. Ginkgo has been cultivated in East Asia for hundreds of years. Numerous reports mention the existence of large specimens, some more than a thousand years old, at ancient temples in Japan and China. The tree was first introduced to North America in 1784 in the garden of William Hamilton at Woodlands near Philadelphia. Mature ginkgos are said to reach over 100 feet in height. Its longevity as individual trees and a species in general can in part be attributed to its exceptional resistance to pests and resiliency to destruction by fire. It is also extremely tolerant of air pollution thriving in the harshest urban environments.
Ginkgo leaf extracts are highly complex, highly concentrated preparations with an average ratio of 50 parts ginkgo leaf to one part of the finished extract by weight. Numerous chemical constituents are found in the extract. Normally ginkgo leaf extracts are calibrated to contain 24 percent flavone glycosides (but may range from 22 to 25 percent) which are a relatively ubiquitous group of compounds found in numerous plant species. Another important compound group in ginkgo leaf extracts are mostly unique to ginkgo — the ginkgolides — including ginkgolides A, B, and C (around 3 percent) and bilobalide (also about 3 percent). As the oldest living tree species on earth, it is no surprise that it would harbor chemical components rare in nature. Perhaps these extremely complex, large molecules have helped it survive for eons. In addition, during the manufacturing process another group of compounds, ginkgolic acids, which are perceived as potentially toxic, are reduced to below 5 parts per million. Given the specific chemical make-up of ginkgo leaf extracts, it becomes clear why you can’t apply the results of studies with Ginkgo leaf extracts to a simple tea made from ginkgo leaves. Numerous pharmacological and clinical studies on Ginkgo leaf extracts have demonstrated a positive effect in increasing vasodilation and peripheral blood flow rate in capillary vessels and end-arteries in various circulatory disorders, varicose conditions, post-thrombotic syndrome, chronic cerebral vascular insufficiency, short-term memory improvement, cognitive disorders secondary to depression, dementia, tinnitus, vertigo, antioxidant activity, among other effects.
As we transition through the seasons, signs of the past blend with what is to come. Cool spring-fed creeks hold for me a reminder of spring; before winter has yet to begin. Perennial and annual wildflowers along creek banks have gone to seed and turned dormant. The leaves of deciduous woody plants fade from green hues to fall colors, whether vibrant or dull. It’s easier to get to the water’s edge, though stick-tights, beggar’s lice, and other hooked, barbed or Velcro-like seeds and dry fruiting bodies will snare your clothing, hitching a ride, choosing you are their seed-dispersal vector.
One plant that hunkers down during the hot weather, then turns lush in spring fed moving water in the Ozark winter is watercress. Bunches of watercress sometimes make their way to groceries or places where specialty vegetables are sold. As a rather hot-tasting mustard, one can only eat so much of it. Watercress is best used as a secondary leaf ingredient in a fresh salad or a great soup vegetable. It is a kindred herb, a neglected free food, best at this time of year before it flowers and produces seed in the spring, at which time the leaves become more pungent and less palatable. By Thanksgiving ,watercress has shed it’s straggly summer growth and its fast-growing leaves are tender, lush and vibrant. Take it from waters that are free from pollutants, as the leaves can uptake toxins and heavy metals from water. Of course, you should wash it well before consuming the leaves.
Botanists now call it Nasturtium officinale, after a few years of suffering through the Latin name Rorippa nasturtium-aquaticum. It is not to be confused with our garden nasturtium with its bright orange and yellow flowers. That plant, Tropaeolum majus hails from the Andes, and borrows its common name from the Latin name of watercress, given their similar flavors, though they are unrelated in every respect. The essential oil in watercress leaves have organosulphur compounds that give them their bite and distinctive flavor.
It is impossible to determine where this plant originates. It occurs in virtually every country with cool fresh, running water. It was observed in America as early as 1630, and was likely already here before Europeans arrived. Here is a plant that defies all cultural and geographic barriers and blurs the line between food and medicine.
Copyright 2013 Steven Foster. Photos created 19 October 2013, Spring Creek, Rockbridge, Missouri
For me the fragrance of fall is that of new beginnings. The metaphor of new beginnings is usually reserved for spring; but I think of spring as a season of awakening. The start of a new school season, the dawn of cooler weather, the inception of fruiting, and yes, the arrival of a new football season, are all new beginnings that I associate with autumn. Somehow the smell of autumn triggers memories for me that in turn spark feelings. Fall fragrances evoke a longing to know when to be still to take-in the embroidery of the chromatic flush that will take us through winter’s dull tones. The season to enjoy the brilliant colors of autumn is upon us.
When we look at total color patterns, big waves of yellow are moderated by orange, and if everything works as predicted, followed by a short brilliant burst of red. However, some of our earliest turning woody plants such as gum trees (Nyssa species) and sumacs (Rhus species) are in the red spectrum, defying autumn color norms. The first big wave of glorious yellows and reds are from sugar maples (Acer saccharum). Color also depends upon the mix of vegetation, where trees grow, and where they originate. The sugar maples, for example, are associated with northern deciduous forests, and often occur on north-facing slopes. Our mixed oak-hickory upland forests usually present a dull pastel of browns and yellows. Trees in valley floors, such as sycamores along water ways, tend to turn earlier than trees on ridge tops.
There is no single, definitive answer to the question of why trees turn color. Much of our understanding is physiological. Healthy leaves with good leaf volume in later September help to predict good autumn color. If we are generally free from rain, wind and overcast skies for the first three weeks of October, we will have better color. We want cool, bright, sunny days with no freezing temperatures. A major factor among a myriad of variables is the diminishing length of the autumn day, hence the amount of daylight. Production of chlorophyll ceases, and as the green chlorophyll degrades, sugars and anthocyanadins (the vast group of compounds responsible for color combinations of fruits, leaves and flowers) begin to dominate the leaves, aided by the variables of moisture and temperature changes. The recipe changes from year-to-year and species-to-species. This is conventional wisdom.
In the last 20 years an entirely new field of study—plant-animal interactions—hints of broader mechanisms, a more wholistic view, beyond mere physiology. Fall colors are integrated in nature signaling to fruit-loving animals and insects that fruits are ready to pluck, thus aid in seed dispersal. In some trees, the colors may send a signal to insect herbivores that feeding time is over. The new science of autumn tree color suggests the process is a mix of defensive, seed-dispersing, signaling, and physiological functions all working in symphonic harmony to create the intricate beauty we enjoy.
When to expect the peak of fall color, you ask? Trying to predict the peak of fall color is not as easy as predicting when the next Full Moon. Autumn color, while falling into a predictable time range is subject to the variables of light, cold, heat, moisture, and the little understood symphony of all of nature working in concert. If you record peak color days over time, predictable patterns will repeat themselves. Short of keeping a journal, our digital devices record the date we snap an image in the metadata of the image itself. I bought my first digital camera in 2004. Since the fall of 2005 in the Ozarks near the Arkansas-Missouri borders my best fall foliage photos (dates as recorded by digital camera) are taken during the last week of October through the first week of November. Therefore, my prediction for peak foliage this year along the counties skirting the state borders is precisely October 26th (give or take a week).
Predictions aside, our role in the process is simply to enjoy the beauty of nature.
Here’s a link to 96 images I took along the Siq at Petra. The Siq is a narrow gorge split between mountains forming the main passage into the Nabataean city of Petra, a UNESCO World Heritage site in Jordan. Along the way one sees an impressive carved water channel and carved symbols of Nabataean gods. The natural sandstone is of spectaular beauty. Petra is an ancient city believed built by Nabataean Arabs around the 300 B.C.E., though remains of a neolithic settlement 10,000 years old are found at this extraordinary site where local Bedouin tribes lived among the ruins into the 1980s.