Dawn Redwoods

CARY'S MAGNIFICENT DAWN REDWOODS

On Wilkinson Ave., just north of the Police Department building, sits a stand of 15 Dawn Redwood trees! They are [in 2019] 19 years old, and stand over 45 feet tall. All are in excellent condition.

This is the Town of Cary's contribution to the effort to prevent the extinction of an Endangered Species. Note that the oak tree in the foreground is dwarfed by the dawns. The oak and the dawns were all planted at the same time in 2000.

These trees were planted in 2000 when the town campus was expanded. Amy Mackintosh and Mark Robinson created the site plan and selected the trees. Ms. Mackintosh now serves as landscape architect for the Town of Cary and Mr. Robinson is a principal of the firm Johnson Hill Land Ethics Studio in Ann Arbor, Michigan.

The story of the Dawn Redwood is fascinating.

Tens of millions of years ago the Dawn Redwood was the dominant species of tree in North Carolina as well as the rest of North America, most of Europe, and the temperate regions of Asia. Long-term variations in the earth's climate, marked by alternating increases and decreases in temperature, caused the species to die off. Fossils of the species remain.

It wasn't until 1941 that the Dawn Redwood was identified as a unique species. Prior to that, botanists had believed that its fossils were Coast Redwood fossils. The Coast Redwood is also a species that thrived millions of years ago, and along the same ranges as the Dawn Redwood. However, not all Coast Redwoods were killed off by climatic variation. Large stands of Coast Redwoods survived well into the nineteenth century along the northern West Coast of the United States and well into Canada. A logging frenzy that lasted from 1850 to 1905 took down 96% of these remaining Coast Redwoods. This destruction was drastically slowed [but not halted entirely] through the partnership of John Muir, environmentalist and founder of the Sierra Club, and Theodore Roosevelt, President of the United States.

A magnificent Dawn Redwood by the lake on the campus of Rex Healthcare at the intersection of Cary Parkway and Lake Pine Drive. Two more Dawns grow near the waterline left of this tree.

In 1941 Japanese paleo-botanist Shigeru Miki, a professor at Osaka City University, was studying what were then classified as Coast Redwood fossils. Dr. Miki noticed a small but significant difference among these samples. In some, branches and leaves grew in alternating rows along their spines. In other samples, branches and leaves grew in directly opposite rows along their spines. Dr. Miki determined that the fossils having branches and leaves growing opposite one another represented a distinct species. He named this new species Metasequoia. Based on the age of fossils, Dr. Miki estimated that the Dawn Redwood had gone extinct about two million years ago.

At about the same time, the people of China were becoming aware of the aggressive tendencies of the Japanese Empire. Many Chinese believed that war with Japan was imminent. Anticipating the need to evacuate large numbers of the population from probable zones of combat, the Chinese government sent scouting parties into the relatively uninhabited and uncharted interior of the country to find suitable areas.

In 1941, one of these scouts named Kan was surveying a remote area of the Sichuan and Hubei provinces in the interior of China. Mr. Kan came across a small stand of trees, the genus of which he had not seen before. The local population called the trees 'water fir.' Kan wrote a brief description of the trees. Three years later, Mr. T. Wang, a Chinese forestry official, happened upon the same grove of trees and collected samples from them. Local villagers told Wang that this stand of trees was the only place that the water fir grew in the province.

A Dawn Redwood in fall color on the grounds of the Garden Supply Company on Old Apex Road.

In 1946, Professor Xiansu Hu, a botanist at the National Nanchang University, and Professor Wan Chun Cheng, studied these samples of the recently discovered trees and determined that they were in fact examples of the genus that Dr. Miki, through his study of fossils in 1941, had named Metasequoia.

This discovery electrified the scientific community. Finding a small grove of living Dawn Redwoods was like finding a living dinosaur colony in some remote and uninhabited region. Dr. E. D. Merrill, director of Harvard University's Arnold Arboretum, was particularly excited by the find. He persuaded Harvard to finance a small expedition to China. Several scientists from Harvard traveled to China in 1949 and met with Chinese scientists, including Dr. Xiansu Hu. This group journeyed to the small group of Dawns found in the interior province, where Dr. Hu collected about a kilogram [2.2 pounds] of seeds. The seeds were brought back to Arnold Arboretum and carefully planted in a protected area.

Dr. Merrill made plans for a second expedition to collect more seeds. Prior to the expedition's departure, Chairman Mao Tse Tung closed the borders of China, barring almost all travel to and from the country and making scientific collaboration impossible. The borders remained closed for almost 30 years.

Dr. Merrill was nevertheless determined to keep the species from going extinct. He sent Dawn Redwood seedlings, germinated from the precious 2.2 pounds of seeds collected by Dr. Hu, to other arboretums around the country. He also sent seedlings to private gardens and estates (whose grounds were professionally managed and maintained) in the United States, Europe, Australia, and some countries in Asia. Many survived and flourished.

There are two [that I know of – there may be more] of Dr. Merrill and Dr. Hu's original Dawn Redwood seedlings growing in North Carolina. One is in the garden of the Biltmore Estate in Asheville. It is the tallest Dawn in the world, measured in 2012 to be slightly more than 130 feet tall. The other is in the Sarah P. Duke Gardens in Durham. This magnificent tree is the darling of the supervisors and volunteers who serve at the gardens. If you ask any of them about the tree, you are assured of a long, delightful, and loving explanation of their Dawn and its history.

The Dawn Redwood is truly a magnificent tree. It is a close genetic cousin of both the Coast Redwood and the Giant Sequoia trees. The Dawn doesn't grow nearly as tall as those West Coast giants (some of which exceed 350 feet in height), but does tower over most other noble hardwoods. In Boston Public Garden, for example, the Dawns [all, of course, no more than 68 years old] are already taller than the centuries-old oaks, elms, and other trees growing there. Coast Redwoods and Giant Sequoias live more than 3,000 years. Scientists disagree on the possible life-span of the Dawn Redwood: estimates range from 500 to 1,500 years.

Two Dawns in winter on private property.

The Dawn Redwood is one of the few deciduous conifers. It grows needles (about ¾ inch in length) instead of leaves. The needles form in springtime, when they are a delicate light-green color. As the year goes on, the needles turn a deep, vibrant green. In fall, the color becomes spectacular. The needles turn a gold/bronze/copper color before falling off. Because of this cycle, landscape architects use the Dawn Redwood as a symbol of eternal renewal. Bruce Kelly, chief landscape architect of the Central Park Conservancy in New York, planted three Dawn Redwoods in Strawberry Fields, the memorial to John Lennon, for this reason.

Cary's effort contributed in a small but highly significant way: the International Union for the Conservation of Nature recently upgraded the Dawn Redwood species' conservation status from Critically Endangered to Endangered.

The species is still, by definition, “in high risk of extinction” in the wild. However, every Dawn planted ever so slightly increases the chances of survival of the species. So if you want to plant a tree (or two, or six, or a dozen!), the Dawn Redwood makes a great candidate. The NC Division of Forest Resources classifies the Dawn as a "recommended street tree." The tree grows fast (Cary's have grown to 40 feet in 17 years), glories in Cary's climate, grows in pleasing pyramidal form, has truly spectacular fall color, and you won't have to rake its leaves.

Note: Many current approved-tree lists do not include the Dawn Redwood or other species that have been discovered and/or revived in recent years. This is because the compilers of these lists have, without consideration, simply adopted one of the several lists published by the dean of American landscape architects, Frederick Law Olmsted, or by his two sons, who inherited and carried on the Olmsted landscape-architecture firm. The elder Mr. Olmsted died in 1903, and the last list compiled by his sons was published in 1930. The Dawn was found not to have been extinct in the mid-1940s. Had the Olmsteds lived to learn of the existence of the the Dawn Redwood, it might very well have been at the top of their lists of approved trees.