Tea Time: Linden Flower Tea

Lindens make great trees for urban areas. A few species and hybrids in particular are commonly planted in parks, yards, and along the streets of cities across the northern hemisphere and have been for decades – centuries even. They cast dense shade, are tolerant of a variety of climates and soil conditions, and are generally easy to maintain. For much of the year as you move throughout the city you live in, you likely pass by dozens of lindens without thinking twice about them. They are ubiquitous, conventional, ordinary, common. Unless they’re in bloom. For a few weeks in early to mid-summer, flowering lindens produce an impossibly sweet fragrance that can’t be ignored. Along with the scent comes the sound of hundreds of buzzing bees collecting pollen and nectar from the pendulous blooms.

Lindens are trees and shrubs in the family Malvaceae and genus Tilia. Around 30 or so species are found in temperate regions across the northern hemisphere, mostly in Europe and Asia. Depending on who you ask, there are between one and three species native to North America. Tilia caroliniana and Tilia heterophylla are considered by some to be varieties of Tilia americana, or American basswood, which is distributed across central and eastern United States and north into parts of Canada. Another common name for linden is lime because words used to refer to the tree in older languages were similar to the word lime. The name basswood comes from the tree’s fibrous inner bark, known as bast.

Linden leaves are generally heart-shaped and asymmetrical with serrate margins. Small clusters of little yellow to white flowers form at the end of a slender stem attached to a narrow, ribbon-like, yellow-green bract. The bract aids in seed dispersal by helping the fruits float on the wind away from the parent tree in a manner similar to the samaras of maple trees. The fruits are small, round, hardened drupes that resemble little peas. The fragrant, nectar-rich flowers are not only favored by beekeepers for honey production, but also have a long history of being harvested for making tea (i.e. tisane). Linden flower tea is said to have a number of medicinal uses and health benefits, all of which I take with a grain of salt. This series of posts isn’t meant to be an investigation into the health claims of plants, but instead an opportunity for me – out of sheer curiosity – to try making tea out of a variety of different plants . If medicinal uses interest you, I encourage you to seek out credible, peer-reviewed sources.

I made linden flower tea from flowers I collected from Tilia cordata, commonly known as littleleaf linden. It was an easy one to find due to its popularity as an urban tree. The natural distribution of littleleaf linden extends from Britain across Europe and into western Asia. Its triangular-ovate shaped leaves are 4-10 centimeters long, glossy green on top, and pale green on the bottom with tufts of orange hairs along the leaf veins, concentrated at the base of the leaf where the leaf blade meets the petiole. The tree can reach up to 21 meters tall and has an oval or rounded-pyramidal shape, though many trees in urban areas are cultivars and can be smaller and more compact.

I harvested the flowers – bracts and all – in late June. It’s advised that they not be harvested directly after a rain (or after being hit by sprinklers), and that they are harvested when the flowers are newly opened. I presume this is because the flowers are at their freshest at this point and will be the best for making tea. I layed the flowers out to dry on a clean kitchen towel on top of a metal cake rack. It only takes 2 or 3 days for them to dry. After drying I removed and saved all the flowers and threw out the bracts and stems, but apparently you can use the entire inflorescence if you’d like.

There are several linden flower tea recipes online. I went with 3 cups of boiling water poured over 1 tablespoon dried linden flowers, covered and steeped for 15 minutes. The resulting tea was an appealing pastel yellow color. I tried it plain as well as sweetened with a little bit of honey. I preferred it sweetened, but unsweetened wasn’t too bad, just a little bitter. It has a floral taste and pleasant smell. Sierra said it tasted earthy, like something she wasn’t supposed to be drinking. Despite that odd review, she said she liked it. Since several sources discussed the calming, sleep-inducing effects of the tea, I made sure to drink it in the evening when it would be normal for me to be feeling sleepy. I suggest you do the same.

More Tea Time Posts on Awkward Botany

Famous Botanists in History: Zhan Wang

Researching last week’s post reminded me of a series of posts that I have been wanting to start for quite a while: Famous Botanists in History. With Metasequoia on my mind, who better to inaugurate this new series than Zhan Wang – the botanist who made the first scientific collection of the living fossil.

From what I can tell, most of what is known about Zhan Wang (at least outside of China) comes from his contribution to the discovery and description of Metasequoia glyptostroboides, and even that information seems to be available largely due to the efforts of some of his colleagues and former students who endeavored to see that Wang be acknowledged for his role in the event. After Wang’s death, a group of his former students wrote a short biography which appeared in the August 2000 issue of the journal Taxon. The biography is written from the perspective of a group of people who greatly admired and respected their teacher and mentor. Unable to find much else written about Wang and his life, the details in this post are mostly taken from that biography. If there are other resources, I would be grateful to have them brought to my attention.

Zhan Wang was born in a remote village in Liaotung Province (now Liaoning Province) in northeast China on May 4, 1911. His birth name was Yishi, but he changed it to Zhan (or Chan) after running away from home in 1932. He developed plant identification skills early in his youth and used those skills to learn about Chinese medicine. He studied forestry in high school. When he graduated in 1931, the Japanese army was in the process of invading northeast China, so he fled to Beijing. There he continued his forestry studies at Beijing University (known today as Peking University). He graduated in 1936, and around that time, Beijing University along with other educational institutions and government agencies in Beijing and Nanjing were evacuating to escape aerial attacks. As Kyna Rubin puts it in The Metasequoia Mystery, “much of Wang’s early career was spent dodging war.”

Zhan Wang went to middle school and high school in Dandong City, Liaoning Province (photo credit: wikimedia commons)

Zhan Wang went to middle school and high school in Dandong City, Liaoning Province, China (photo credit: wikimedia commons)

Zhan moved with Beijing University’s Agricultural College to the Shaanxi province where he took a position as professor of dendrology and forestry. Wang’s students say that he preferred to teach his classes outside where the students could have “hands-on experiences” directly observing the morphology and ecology of plants. He “told stories about the species,” encouraged “looking, touching, tasting, and chewing,” and found many other ways to integrate botany and ecology in his courses. One way he helped students understand plant ecology was by grouping plants into categories with clever nicknames such as “mountain climbers” (plants found in cool climates), “greedy boys” (plants with high nutrient demands), “thirsty guys” (plants with high water demands), and “desert fighters” (drought tolerant plants).

In 1943, Wang became a Forest Administrator for the Ministry of Agriculture and Forestry, a position which included doing forest surveys in remote areas. On an expedition to Shennongjia in the Hubei province, Wang was stricken with malaria and had to stop in Wanxian County. There he met an old classmate of his, Longxing Yang, who told him of an unusual tree, which was later described as Metasequoia glyptostroboides by Wanjun Zheng and Xiansu Hu thanks to the initial collections that Wang made in July 1943. Despite being left out of some of the accounts of the discovery, Wang’s students claim that he didn’t complain and was more concerned about the tree’s continued survival, believing that “discussing the past discovery of a new species is not as important as investigating how a living fossil species will survive in the future.” His students were admonished to “focus on the species’ protection and its habitat.”

Wang’s position as Forest Administrator was short-lived; however, over the next several decades he continued to teach dendrology and forestry at several Chinese universities. Much of his research efforts were focused on sorting out the taxonomy of the willow family (Salicaceae), a highly complex plant family. He collected willow species throughout China and, with the help of his colleagues, described more than 90 new species. He also became very concerned about deforestation and “focused his attention on devising scientifically sound harvesting methods and successful regeneration processes.” Despite his work being largely restricted to China and (as his students claim) “receiving little credit elsewhere,” similar approaches to the sustainable forestry methods that Wang preached are “widely recommended and accepted today in western forestry practices for ecosystem management.”

Zhan Wang described many new species of Salix. Salix wangiana var. tibetica is a species that was described by and also named after Wang (photo credit: Flora Republicae Popuaris Sinacea)

Zhan Wang helped describe dozens of species of Salix that were new to science. Salix wangiana var. tibetica is a species that was described by and also appears to be named after Wang (photo credit: Flora Republicae Popularis Sinacea)

In the 1950’s, Wang began carrying out research at Changbai Mountain Nature Reserve high on the Changbai Mountain located in northeastern China on the border with North Korea. His efforts were interupted by the Cultural Revolution, a period that lasted from 1966-1976. As soon as that had passed, Wang and colleagues began working to establish the Changbai Mountain Forest Ecosystem Research Station. Wang became the first director of the station when it was approved and funded in 1979. Wang and his research team worked to establish “baseline information on the area’s flora, fauna, vegetation, and soils,” and in three years time had amassed enough research to warrant over 100 published papers. Due to the efforts of Wang and his team, the Changbai Mountain Nature Reserve gained inclusion in UNESCO’s Man and the Biosphere Program.

Wang’s students write that Wang viewed “Changbai Mountain as his home” and “believed that his life belonged to this mountain region.” His wish was to one day have his ashes “spread throughout the wilderness” of this mountain. After his death on January 30, 2000, his wish was carried out. “He will forever be with his beloved plants and forests in this important site of plant diversity, and now, place of rest.” Wang was survived by his three daughters; his son committed suicide during the Cultural Revolution, and his wife died in 1992.

In the adoring words of his students, Wang had a “kind, gentle character and contagious enthusiasm for science and nature” and “his contribution to botany went far beyond what is available in print. His footprints from exploring plants in China can be found in almost every province.”