The essay “The Role of Stress in Tea Growth and Manufacture” by Sanwar M. Changoiwala appeared in CHA DAO on March 27, 2007. In his article, Changoiwala noted that the flavor of harvested tea is enhanced when the tea plant is subject to adverse growing conditions. High elevation, cold temperature, drought, poor soil, frost and insect damage, and ultraviolet radiation were cited among the environmental stresses that affected tea plants and induced better taste in the leaves picked from such plants. The increasing appreciation of rare tea has encouraged the production of “handpicked,” “organic,” “wild,” and “high mountain” tea. Such designations are meant to inform and entice, but they are also descriptions that reflect the stress under which tea is grown and harvested. Moreover, inherent in such branding is the promise of tea with distinctive flavor.
Many of Changoiwala’s points regarding the affect of growing conditions on the quality of tea were first observed by Chinese horticulturalists over twenty-five hundred years ago. As with modern agricultural techniques, their conclusions were born of long experience, practice, investigation, and the habit of recording information in their vast writings on tea. The most famous of all tea books is the Chajing 茶经, the Classic of Tea, by the Tang poet and tea master Lu Yu 陆羽 (733-894 A.D.). The Chajing was the first literary work to fully describe the tea plant as well as to detail specific planting conditions that stimulated better flavor in the leaves.
Beginning with the words, “Tea is from a splendid tree of the south,” Lu Yu brilliantly conjured up an image of the stately, luxuriant evergreen, a semitropical in full spring flush, limbs and branches graced and bright with glossy leaves. Lu Yu’s description of tea as a tree had the feel of legend, an ambiguous condition between fact and fiction, for everyone understood that tea was a tree but all knew tea to be a bush. In Tang imperial China, tea gardens and estates were seas and oceans of verdant tea, rolling from afar in low sets of waves, vast hedgerows lapping up in small, dense bushes that stood pleasantly rotund and appealingly fresh. Thus, the dichotomy propounded by Lu Yu prompted the question “How is a bush a tree?” The answer lay in the discovery of wild tea in antiquity and the transformation of the tea plant through stress.
Hoary, wild tea trees of exceptional age, some hundreds, even a thousand years old, attained huge girths and scores of feet in height. In Neolithic times, tea was harvested by climbing the length of the tree along branches and out limbs to pick its leaves. A less dangerous and more productive method was to cut down the trees so as to more easily and completely gather the tea. The chopping of trees was beneficial in yet another way: the stress of felling forced shoots from stumps and roots. At ground level, the forced foliage was easy to pick, and the stress of repeated pickings as well as periodic pruning retarded growth. Applied to seedlings and shrubs, the technique fostered tea as a cultivated, low and compact bush.
Cultivated tea was planted in the gentle hills and fertile valleys of the subtropical south. However, it was known that superior tea was produced on the more temperate slopes of mountains and scarps. The chill of higher altitudes, reinforced by wind, cloud, and mist, stunted the growth of tea plants, particularly at night when temperatures dropped precipitously and sharpened stress. High elevations were not only cooler in clime but also clearer and exposed tea to the full radiance of the sun. In the Chajing, Lu Yu recognized the importance of solar exposure on the quality of tea and wrote, “Tea grown on shaded mountain slopes and valleys is not worth picking” but the “…leaves of plants grown on sunny cliffs…are of superior quality.”
Mountainous terrain was steep and sloped, eroded but stony like the soil found at the base of cliffs: low in nutrients, well-drained, and prone to drying out. Lu Yu stated in the Classic, “The best grade of soil for growing tea contains disintegrated stone. Soil of middle grade contains gravel. The lowest grade is yellow earth in which all that is planted bears no fruit; the plants put forth but sparse growth.” After gravelly soil, “yellow earth” or dirt with organic matter was the least favorable ground in that it held moisture and nutrients. Stony soil was best for growing tea precisely because it placed stress on the plant.
Although he considered estate-grown tea excellent in quality, Lu Yu declared that “Wild tea is of superior quality; estate-grown tea is next.” Wild tea was the rarest tea. It was even rarer than imperial tribute -- tea that was grown, processed, and reserved exclusively for the emperor. In the mind of the cognoscenti, however, nothing exceeded the quality and rarity of tea gathered from the wilderness. Stories abound of tea masters wandering remote mountains, searching for wild tea. Discovering a few small trees, they picked the choicest shoots and buds, carefully culling the leaves like jewels of jade.
Yet even precious wild tea had to meet the strict criteria that Lu Yu set out in the Chajing. According to tradition, tea was picked in the late winter and early spring, during the second, third, and fourth lunar months. Harbored within the tea plant all winter long, once-latent growth burst forth in the spring, a bright bloom of shiny green buds and leaves:
“The tea shoots…are first selected from those that resemble fern stalks four to five inches long. The shoots should be picked while the morning dew is still icy cold. Tea buds issue from the lush shoots at the crown of the plant. There are shoots of three, four, and five stems. Select the pointed buds from the middle stem to pluck, then pick them. Do not harvest tea on rainy days. Do not pick on clear days with clouds. Pick tea only on clear days.”
As Lu Yu further noted, the harvest was a double sequence: “leaves that are picked early are called cha; those picked late are called ming…” The first flush yielded cha 茶, buds and leaves that were tender, succulent, and tasty. But as fine as these leaves were, there was even greater anticipation of the second flush. Harvesting tea – picking and plucking the first spring flush – stressed the plant and promoted a later, secondary growth of smaller, more delicate leaves. In tea, the gathering of the second flush produced ming 茗. Quite distinct from cha, the leaf of ming was evermore flavorful: ambrosia in the mind of a tea master.
The origin of the words cha 茶 and ming 茗 is interesting but historically expansive and convoluted. Sufffice it to say that the etymological and epigraphical roots of cha and ming date to the Han dynasty and earlier. Furthermore, the terms cha and ming are intimately associated with the formative herbal and culinary traditions of antiquity, especially the use of sowthistle known as tu 荼 from which the character cha 茶 was derived and to which the bitter taste of tea was likened.
In ancient connoisseurship, cha and ming came to convey not only distinctions between the succession of spring harvests but also expectations of important differences in quality and flavor. In the historical context, cha and ming as horticultural terms showed that tea production had become complex early in time, progressing from simple foraging in the Neolithic age to intensive cultivation in the Warring States period, a time marked by the purposeful application of stress to stimulate high yield in tea as well as high quality. As agricultural techniques progressed, there was a simultaneous cultural and culinary advance. The development of the words cha and ming revealed that tea drinkers had become more discriminating and sophisticated. Teas of remarkable character and complexity changed tea from a mere beverage into an aesthetic pursuit until throughout society, even among the least pretentious and humble, the serving of tea often prompted the knowing query “Is this tea cha 茶 or ming 茗? ”