Sudden Stratospheric Warming Upsets Polar Vortex

©2013 Steven Foster

Pacific-Waves-96676 copy_1 copyThe jonquils are fooled again.  Up they pop with the early week warm-up, only to be beaten back down by cold weather at week’s end. What’s up with the schizophrenic winter weather? Our fluctuating winter weather is due to a very specific atmospheric event called “sudden stratospheric warming”.  We live in the troposphere, a thin layer of atmosphere about 7 miles high, where our weather occurs. Above the troposphere is the stratosphere which stretches about 15-18 miles above the earth’s surface. Usually there is little air exchange between the icy cold stratosphere and the troposphere.

Around the New Year, a massive storm off the coast of Japan and the Kamchatka Peninsula in the north Pacific, stretching 1,400 miles across, and over seven miles high, punched energy up into the stratosphere allowing warmer air to flow upward. The cold thin air in the stratosphere had to go somewhere and it flowed down into the coldest air above the Arctic circle. Picture the coldest polar air like the bubble in a level or an unbroken egg yoke in a frying pan. Above that cold sink of air is the polar vortex, air patterns that spin around that bubble of coldest air. The sudden stratospheric warming event caused a weakening of the stratospheric vortex which wobbled downward to disrupt the polar vortex.  Energy release causes an equal and opposite reaction.

The disrupted broken egg yolk of the polar vortex caused an energy wave that bumped into the polar jet stream. We live between the polar jet stream and the subtropical jet stream both of which generally run west to east (though can be highly variable). Last year we had a very mild winter because the polar jet stream basically sat at the U.S. Canada border and flowed straight west to east. Polar air stayed to the north of it.

Now the polar jet stream, bumped by the wobbling polar vortex creates big waves in the jet stream undulating across the continent. That means for the next month, the weather will be predictable. We will have 3 or 4 days of unseasonably warm weather followed by 3 or 4 days of cold weather.

By the way, this  atmospheric conspiracy is linked to sun spots.

Cycles of Nature

The cycles of nature dictate everything is in a constant state of change. I write from  Austin, Texas, where the cycle of change means that for the third time on record, not one drop of rain fell to the earth in the month of November. If you look at the vegetation around here, it’s quite clear that this place is not far from being a desert.

Hundreds of miles south of Eureka Springs, rumors reach me that the Great Passion Play has its gates shuttered and chained, a victim of change or more likely, the inability to change. Nature adapts. From my home on Spring Street, with a view toward the eastern horizon, every sunrise and every moonrise is shadowed by the Christ of the Ozarks. The sun, the moon, sunny days, rainy days, rainbows, bolts of lightening and dark days are all wrapped-up in the outstretched arms of a manmade object that stands oblivious to changing nature.

In my late teens I recall searching for rare orchids with a friend in northern Maine in a remote area not far from the Canadian border. We walked along a railroad bed that had been abandoned five years earlier. I was struck by how in just five years that thoroughfare once kept clear of vegetation by racing tons of iron had been completely swallowed-up by lowly vegetation. One could not imagine that trains roamed the same trail just a few years earlier.

As I flew into Austin, knowing that the city’s commercial airport had in recent memory been an Air Force base, again I was struck by how the runway remnants no longer in use, once under the mighty whirling wheels of military jets, are now crags of black cracked asphalt hidden beneath waves of grass, weeds, and wildflowers, enveloping and overtaking the once invisible asphalt.

If the rumors are true, may I soon be staring toward the east and watching the sun and moon rise over a silhouette of vegetation once known as the Christ of the Ozarks? If that’s the case, I will smile and say, that’s the work of God.

©2012 Steven Foster

I’m Dreaming of a Bright Christmas

Carroll County Arkansas in the year 2077.

I’m dreaming of a bright Christmas—sunny with temperatures in the low 70s. The iconic “White Christmas” is so 1940s, forget the fact that Bing Crosby’s version of Irving Berlin’s song is the best-selling single of all time. We must look on the bright side of global warming or the more politically correct “climate change.” We just need to change our perspective.

Speaking with my 83-yr old dad in Maine over Thanksgiving, he remarked that as a kid, he and his friends were always skating by Thanksgiving. I reminded him, that we—his kids—were also skating by Thanksgiving! During my Maine childhood a white Christmas was a given. Now, ponds and lakes barely hold ice in a Maine winter. A white Christmas is merely a historical song from 1941.

It is true that all scientists actively involved in climate change research do not agree that the rise of global temperatures is the result of human activity. No, of 1,372 climate change scientists surveyed in 2010, only between 97–98 percent of scientists believed that global warming was caused by human activity. That leaves between 27-41 non-believer scientists (the 2-3%) that conservative “I told you so” faux journalists and faux policy makers can parade in front of cameras and hearings to dispute the reading on your thermometer. Why act when instead you can make jokes about Al Gore inventing the internet?

This week 17,000 attendees are debating data and policy at the 18th United Nations Conferences of the Parties on Climate Change in Doha, Qatar. It’s the perfect venue since Doha is a man-made desert oasis in a tiny country with the highest per-capita carbon emissions in the world.  Not to worry. The conferees won’t do anything but talk. On November 27th, the Intergovernmental Panel on Climate Change in their fourth assessment report, said whoops, we were wrong. Sea levels are rising 60 percent faster than our previous projections. Bye-bye Manhattan. Get to New Orleans while it’s still there.  Look on the bright side, who doesn’t want to turn down the heat and throw open the windows this winter? I’m dreaming of a bright Christmas!

Ice Ribbons and Frost Flowers


By Steven Foster |

What are those ribbons of ice traveling up the stem of roadside plants that you may have noticed on a recent early morning?  They are “frost flowers”, “ice flowers”,  or “ice ribbons” and are found on two plant species at this time of year native to the Ozarks. Those seen on plants in ditches or at the edge of a road are probably from White Crownbeard, Frostweed or Tickweed (Verbesina virginica). A late blooming member of the aster family, it sports ragged white flowers in flat-topped clusters. It’s a plant you probably won’t notice until now—the moment of the first few hard freezes of autumn. The frost flowers form during the first few hard frosts as capillary action draws moisture up the vascular bundle of moist living tissue fed from the roots, then the watery sap freezes, expands at right angles and transforms along the stem into extruded crystals ribbons of beautiful, layered, ice formations.

Another plant found in woodlands, American Ditty (Cunila origanoides), which grows in dry, wooded habitats mostly on west or south-facing slopes, also produces frost flowers. You probably have to go a little out of your way to see them, unless you drive along a forested dirt road early in the morning. This little oregano-scented mint family member is common in our woods. On the first frosty morning of autumn, the still active roots send cell sap toward the stems, now cracked and beginning to die back to the ground. As the sap from the root tries to make its way up the cracked stems, the freezing air turns the moisture-laden sap at the base of the stems into fluted, twisted, layered ribbons of ice that look like Christmas ribbon candy. This phenomena usually occurs only during the first few frosts of the year, though American Dittany can produce frost flowers for several weeks, depending upon soil moisture and weather conditions. Of course, another plant that is a definitive barometer of the season’s first hard freeze is the tomato. If one morning your tomato plants suddenly turn black then likely we’ve just had our first frost.


Freaks of Nature

Sassafras leaves
An unusual five-lobed Sassafras leaf

© Steven Foster

In 2009 Holiday Island resident and Eureka Springs Independent reader, Leah Nelson, noticed an extraordinary leaf on a sidewalk in Rogers, Arkansas—a giant sycamore leaf that was 16 ½ inches wide, and 13 ½ in. long, more than twice the normal size. This fall at Black Bass Lake I found a small group of Sassafras trees with leaves that were far from normal. Usually Sassafras has three types of leaves— simple oval leaves, mitten-shaped leaves (with one prominent lobe), and three-lobed leaves. Sassafras leaves are “always” longer than wide. On these trees, a large percentage of leaves were 5-7-lobed, and up to three times as wide as long.  Back in the early 80s I wrote about an Ozark Witch Hazel (Hamamelis vernalis) plant that I found that was brilliant scarlet red. It’s usually yellow to orange-tinged. A plant breeder in up-state New York saw my article and traveled to the Ozarks just to see the plant. He collected it, propagated it and offered it to his customers. These are examples of what horticultural breeders refer to as “sports”—variations from a plant’s “normal” morphological features. It’s all part of the package that nature delivers as endless variation.

It is this endless variation that horticulturists exploit to bring unusual or new plants to gardens. The famous plant breeder, Luther Burbank (1849-1926), gave us the giant Idaho potato (the Russett-Burbank potato). Before that one could hold a handful of potatos. Inspired by Charles Darwin’s 1868 book The Variation of Animals and Plants under Domestication, Burbank  planted dozens of acres of daisies, then walked up and down the rows, selecting a handful of “sports” from which to collect seed for propagation. The rest of the field was plowed under. From those selections the Shasta daisy was born. These types of variations usually are not described in field guides. They are freaks of nature, genetic twists of fate, or perhaps some inexplicable response to the environment. Who knows! We just hope that when we find such mutations that they are not induced by man-made chemicals unleashed to the air, soil, and water or from genetically modified organisms.  Let Nature work her own wonders.

Dr. Shiu Ying Hu

Shiu-ying Hu, PhD: 1910–2012 

by Steven Foster

Published by the American Botanical Council in HerbalGram 95:74-76

On May 31st, 2012, the Chinese University of Hong Kong posted an obituary of Prof. Hu Shiu-ying, PhD (Shiu-ying Hu), announcing the passing of the eminent economic botanist and taxonomist. She died at the age of 102 on May 22, 2012, at the Prince of Wales Hospital, Hong Kong. Her obituary appears on a website dedicated to the memory of her remarkable life and work.1

Dr. Hu, Emeritus Senior Research Fellow of the Arnold Arboretum of Harvard University, spent most of the last 20 years in Hong Kong, where she served as Honorary Professor of Chinese Medicine, Honorary Senior Research Fellow of the School of Life Sciences, and Senior College Tutor of Chung Chi College at the Chinese University of Hong Kong. In a career stretching nearly 8 decades, Dr. Hu was active past her 100th year. Dr. Hu became the leading expert and monographer of the genera Philadelphus or mock orange (Hydrangeaceae), Hemerocallis or daylily (Liliaceae), Paulownia or princess-tree (Paulowniaceae), the mallow family (Malvaceae), and Ilex or hollies (Aquifoliaceae). Considered a leading world expert on hollies (Aquifoliaceae), the American Holly Society created an award in her name in 1992, for which Dr. Hu was the first recipient. She was affectionately nicknamed “Holly Hu.” In addition, Dr. Hu made significant contributions to the taxonomy of major plant families including the orchid family (Orchidaceae), mallow family (Malvaceae) and aster family (Asteraceae), among others. It is rare to read a paper on Ephedra (Ephedraceae), Eucommia (Eucommiaceae), Leonurus (motherwort, Lamiaceae), Panax (ginseng, Araliaceae), and other medicinal plant groups that does not contain citation to Dr. Hu’s various papers on those plants. In 2008, Dr. Hu was also the first, and so far only, recipient of the American Botanical Council’s Lifetime Achievement Award. 2,3

Dr. Hu was born in February 1910, during the Qing Dynasty in a small village on the southern bank of the ancient course of the Yellow River. In her magnum opus, Food Plants of China, she describes the farmland as poor in condition, reclaimed from a swamp. In summer months, floods and storms destroyed all crops and predictable famines ensued. In her youth, it was there that Dr. Hu gained firsthand knowledge of famine foods and medicinal plants.

She was raised in a communal homestead shared by descendants of her paternal grandparents. At times, the family survived by foraging for wild foods. Her mother gave birth to three daughters and two sons. Shiu-ying Hu and one brother were the only two who survived in a rural region of China with an infant mortality rate of 50%. Soon after her birth, Shiu Ying Hu fell ill, and her mother sent her father to a nearby village to obtain an herbal medicine to save the young girl’s life. Like most peasants in China, he had no shoes. He tied reeds to his feet to make the journey, and trudged through snow to get the herbal prescription that saved Dr. Hu’s life. When she began her botanical studies in the 1930s, Dr. Hu asked herself the question, “What is the herb that saved my life?” That question remained unanswered, but inspired Dr. Hu to apply herself to the study of plants to improve the well-being of rural people in China.

A stroke of good fortune provided a scholarship which allowed her to attend Mary Stevens Girl’s High School, a boarding school in Xuzhou run by Presbyterian missionaries. After graduation, she attended Ginling College, a small liberal arts and sciences college in Nanjing. There, for the first time in her life, she enjoyed a bowl of rice. Although interested in agriculture courses, which were not offered, she studied biology and sociology in hopes that it would offer her the opportunity to pursue her cardinal interest — helping to serve the people in rural China.

After finishing her undergraduate degree at Ginling College in 1933, she began work toward a Master’s degree in botany at Lingnan University in Guangzhou. Among her teachers was Prof. F. A. McClure, a leading 20th-century botanical expert on bamboos. In pursuit of food and medicinal plants of rural peoples, she prepared her thesis, “The Chinese Esculent Plants Used for the Conservation of Health.” She gathered data from herb collectors, shopkeepers, Guangzhou homemakers, Taoist monks and nuns residing in Luofu Shan, as well as drawing on her own personal experience.

Soon after finishing her Master’s degree in June 1937, the Sino-Japanese War broke out and Dr. Hu became a refugee.  In January of 1938 she arrived in Chengdu, Sichuan, having accepted a teaching position at West China Union University, where she remained for eight years. Her monthly salary was three bushels of rice. During this period she collected plants in the Emei Mountains (Mt. Omei) famous for medicinal plants, and lived two summers with Sino-Tibetan ethnic groups including the Qiang and Jiarong. The Jiarong live in the territory of the giant panda.4 Today colleagues find it remarkable that she collected plants in this remote and rugged region of China, which even now can be reached only by off-road vehicles or on horseback. She traveled on foot, sometimes alone in the wilderness for months at a time. During her long life, she collected over 180,000 herbarium specimens.5

In March 1946, Dr. Hu received a telegram from Radcliffe College inviting her to apply for a graduate fellowship for a doctoral program at Harvard University under Professor Elmer D. Merrill, a leading American expert on Eastern Asiatic botany who in the early 1940s had returned to the United States from the Philippines following the Japanese invasion. She received the fellowship, despite being told that Harvard “didn’t take girls.” Two American friends helped provide money for her travel to Boston. Dr. Hu arrived in the United States on August 2, 1946, with a small suitcase of clothes and two large suitcases of plant specimens. In Food Plants of China (2005), she wrote, “The change of lifestyles from China to America was to me like a complete metamorphosis is to insects. Everything was new.”

Dr. Hu was the last student of Professor Merrill, and was a student in the final class of Harvard University’s Gray Herbarium Director, Merritt Lyndon Fernald. In 1949, Dr. Hu received her doctorate, becoming the first Chinese-born woman to receive a PhD in botany from Harvard University. That was also the year that Mao Zedong’s victory over the Kuomintang in China’s Civil War resulted in the creation of the People’s Republic of China. Subsequently, China became closed to the West.

Upon graduation, Dr. Hu dreamed of working for the United States Department of Agriculture. However, she could not obtain a job there. Only Harvard University offered her a position. Later, she was to discover that the Harvard position was actually more prestigious. For the next 3 decades, Dr. Hu worked tirelessly on the taxonomy, phytogeography, and economic plants of China based on collections at the Arnold Arboretum, the Harvard University Herbaria, the New York Botanical Garden, and the US National Herbarium, among other collections. One result of the work is the Hu Card Index, a compilation of 158,844 index cards for Chinese plant names produced by Dr. Hu and her staff, representing the botanical literature on Chinese plants from 1753-1955.6

Five-time Academy Award winner, composer, conductor, and pianist John Williams has been accused of being a tree hugger. Best known for his movie scores, his foray into serious classical composition includes his three “tree songs,” one inspired by a magnificent specimen of Metasequoia or dawn redwood (Taxodiaceae) at Harvard University’s Arnold Arboretum to which Dr. Hu provided William’s a personal introduction. A redwood-relative known only from the fossil record until the 1940s, Williams’ treesong, “Dr. Hu and the Metasequoia,” honors the tree and the Chinese graduate student who planted it in 1949 — Dr. Shiu Ying Hu. Dr. Hu’s service to others and heart-felt enthusiasm inspires.

Explaining his inspiration in an interview with RTHK TV’s “Success Stories,” biographical documentary on Dr. Hu, Williams said, “The tree seems to be almost intelligent…If you look at it long enough it seems to be speaking to you with the wisdom of age and great intelligence…I just love this tree and I love this woman and I thought it might be a nice idea for a musical piece. Dr. Hu is a brilliant scientist, a very attractive woman with a sort of spiritual connection with plants…She knows the plants and they are like children to her. This woman has a spiritual aura about her which is very still and penetrates very deep into her subject almost like a religious person for me.”7

Although working in the pinnacle of botanical academia, Dr. Hu never forgot her Chinese peasant roots. She served as a liaison between the Western world and China during the first two decades of Communist China’s closure to the West. At her own expense, she provided botanical literature and paid membership fees to international scientific societies for Chinese colleagues and students. Through the years, her frugal lifestyle enabled her to provide scholarships, living quarters, and money for dozens of Chinese students to study in America and elsewhere. Her home was Brookline, Massachusetts, but as she was fond of reminding colleagues, her heart always belonged to China.

From September 1968 to June 1969, she served as a Senior Lecturer in the Department of Biology at Chung Chi College, Chinese University of Hong Kong, while continuing her work on the flora of Hong Kong. Once China opened up to the West in the mid-1970s, Dr. Hu made numerous return trips to China, greeted with the deepest respect from China’s scientific community, like a revered sage.

Dr. Hu dedicated her life to improving the life of the Chinese people through her love of plants. China, in turn, honored Dr. Hu’s service. Dr. Hu was appointed Advisor to the Sun Yat-sen Botanical Garden in Nanjing, Honorary Professor of South China Agriculture University in Guangzhou, and Advisor to the Fairy Lake Botanical Garden in Shenzhen. She was instrumental in the establishment of the School of Chinese Medicine at The Chinese University of Hong Kong. She also created a new environmental awareness in Hong Kong by insisting that large trees be incorporated into the campus design, rather than cut down. In 2001, she was awarded the Bronze Bauhinia Star by the Government of the Hong Kong Special Administrative Region.

Her many decades of tireless dedication produced fruits mirroring the towering heights of the Metasequoia tree. Dr. Hu authored more than 160 scientific papers.  She is the author of numerous books, notably her magnum opus, Food Plants of China (The Chinese University Press, 2005), as well as An Enumeration of Chinese Materia Medica (The Chinese University Press, 1980; 2nd ed. 1999) and The Genera of Orchidaceae in Hong Kong (The Chinese University Press, 1977), among others.

In recognition of Professor Hu’s international contribution to botanical science, the School of Life Sciences of The Chinese University of Hong Kong has established an endowment to expand and relocate the University’s Herbarium in the School of Life Sciences, now renamed the Shiu-Ying Hu Herbarium. Information is available at the Shiu-Ying Hu website, set up to honor her memory and accomplishments and includes her obituary, biography, tributes, photos, and many external links.1

Dr. Shiu-ying Hu’s remarkable academic eminence was borne of her consistent, unassuming humility and impressive dedication to work. She studied with some of the most noted botanists of the 20th century, yet her affable personality and simple demeanor erased awareness of all lines of social class structure. Although she counted heads of government and famous composers among those who sought her acquaintance, her ability to listen to anyone earned her friends in teachers and in students — and lifelong friends among all people, from ethnic minorities of Sichuan and Tibet to the herdsmen of Inner Mongolia, the herb collectors of Yunnan, monks and nuns of famous Taoist and Buddhist temples, shopkeepers of Guangzhou, and three generations of botanists from around the world.  In China she was known as “Grandmother Plants.” —Steven Foster


1. The Chinese University of Hong Kong website. Obituary. In Memory of Professor Shiu Ying Hu. May 31, 2012. Available Accessed July 17, 2012.

2. Anon. Remembering Professor Shiu-Ying Hu. Harvard Gazette. May 31, 2012. Available at: Accessed July 17, 2012.

3. Anon. Remembering Professor Shiu-Ying Hu. The Arnold Arboretum of Harvard University website. May 30, 2012. Available at: Accessed July 17, 2012.

4. Hu SY. Food plants of China. Hong Kong: Chinese University Press; 2005., p.14-18.

5. Cheung S., Executive Producer. Success Stories: Dr. Hu Shiu-Ying [DVD Video]. Honk Kong: RTHK TV Programme Series. Intercontinental Video Limited. 2005, 46 min.

6. The Arnold Arboretum of Harvard University. Flora of China Project records, 1953-1977: Guide. Archives II G-1. Available at: Accessed July 17, 2012.

7. Williams, J. Interview in: Cheung S., Executive Producer. Success Stories: Dr. Hu Shiu-Ying [DVD Video]. Honk Kong: RTHK TV Programme Series. Intercontinental Video Limited. 2005, 46 min.


The Mysteries of Autumn Color

Autumn foliage at Sweet Spring

© Steven Foster

This year fall colors came in waves. First a wave of glorious yellows and reds from Sugar Maples (Acer saccharum) planted around Eureka Springs, Arkansas. I couldn’t help but notice that the Sugar Maples planted along the sidewalk in front of the Best Western Eureka Inn at the top of Planer Hill showed their colors and dropped their leaves before the wild Sugar Maples in the forest directly across the street even began to turn color. Same for the Sugar Maples along Spring Street. Those planted along the street have dropped their yellow-orange leaves, while those in the adjacent woods have a glorious color display of orange to burgundy leaves, dominating the current color trend. So what is the difference between the colors and timing of the planted Sugar Maples and wild Sugar Maples? I suspect it is some type of genetic clock trigger. Which begs the question, how are autumn tree colors formed?

There is no single, definitive answer to the question of why trees turn color. Much of our understanding is physiological. The 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 convention wisdom.

In the last 20 years an entirely new field of study—plant-animal interactions— hints of broader mechanisms, beyond mere physiological changes in the leaves. Fall colors are integrated in nature, signaling to fruit-loving animals and insects that fruits are ready for harvest, thus aid in seed dispersal. In some trees, the colors may send a signal to insect herbivores that feeding 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 a symphonic display of intricate beauty. Our role in the process is simply to enjoy it.