Growing Redwoods in Atlanta?

Recently my husband has been suffering with a frozen shoulder. As is typical with such maladies, the treatment may be worst than the illness. However, typical of living with me, his interactions in the world provide fodder for my columns. This week he came home from physical therapy with a question. Someone at the clinic wanted to know, “Can you grow a Redwood in Atlanta, Georgia?”

Of course my first thought, and question was, “Did you mean Redbud?” A Redbud is a lovely understory tree that does very well in Atlanta – both as a tree for wild habitat restoration, and as a street tree.

“No”, he responded. “They want to grow a giant Redwood tree, like the ones in California.” Well this seemed a pretty unlikely candidate to me. Even if you could grow such a tree here, would you want to? I thought I had better do some research before I responded. Here is what I found out.

Where do they grow in the wild?
Unlike many North American trees such as Oak Quercus L. and Maple Acer L., of which one species or another grow natively in virtually every state, the two species we think of as Redwoods (both Redwood Sequoia sempervirens known as the California coast redwood, and Giant sequoia Sequoiadendron giganteum also known as the Sierra redwood) only grow in a very small region of the west coast.

S. sempervirens is found in a narrow band along the coast of Northern California and Southern Oregon, and S. giganteum grows only on the west slope of the Sierra Nevada in California.

© Photographer: Michael-john Wolfe Agency: Dreamstime.com

Does this mean that they can’t grow elsewhere?
Apparently not. According to the website of the American Park Network, which provides information about Sequoia and Kings Canyon national parks, fossil remains indicated that these trees grew worldwide prior to the last ice age.

Welker's Grove Nursery in Auberry California is actively growing and shipping saplings all over the country. They recommend the Giant Sequoia especially as a good tree for privacy screens and windbreaks. In containers, they can be maintained at a manageable size, using bonsai techniques of root and branch pruning. However, the climate of North American is substantially different than it was 175 million years ago. To grow these trees successfully outside of their current native habitat will require some effort.

What do these plants need to thrive?
The Redwood forests in northern California thrive on the cool moist fog belt of the region. Giant Sequoia grow in a small region on the west slope of the Sierra Nevada range, which is constantly watered by mountain run-off, streams and springs. Both species require deep well drained soil and plenty of moisture. This means that in the Piedmont region of Georgia where I live, the clayey soil would require substantial amendment.

In addition to soil requirements, they are very susceptible to drought and drying from wind. Unlike many plants that prefer a good soaking followed by a chance to dry out, these require constant moist soil. On the other hand, they can not tolerate standing in water, or mud, so planting on a riverbank is not a good solution. In our region, it seems the only way to ensure adequate moisture will be with irrigation, and probably with its own separate zone and different watering schedule than you other plants.

If growing in a container, you should be aware that these trees can suck up all of the moisture in less than a day, and once the roots start to wither, you are sunk.

What to expect
Compared to our southern Longleaf pine Pinus palustris or Loblolly pine Pinus taeda with heights 120 and 100 feet respectively, the redwoods are giants. Giant Sequoia will grow to 200 feet at maturity with a 40 foot base. Redwood will reach 250 feet with a 22 foot base and is generally thought to be the tallest tree in the world. Specimens of both have been found in the wild that far exceed these dimensions. In addition, you can expect growth of 5 feet or more in height per year!

The Giant Sequoia is not as tall but more broad than the Redwood, and in terms of volume (height and girth), this is the largest living organism on earth.

Photo credit © Photographer: Amelia Takacs Agency: Dreamstime.com

In addition to providing several of the specimens on the world largest tree list (the largest living sequoia is 275 feet tall and 32 feet in diameter) these trees are also the longest lived. Some have been estimated at 2,000 to 3,000 years old.

What’s in a name?
Sequoia is named for a man with the same name (sometimes spelled Sequoyah) who was the son of a Britich merchant and a Cherokee woman and also the inventor of the Cherokee alphabet. Sempervirens is from the latin “semper” meaning always and “vivere” to live. Thus it means evergreen.

The Giant Sequoia’s scientific name of Sequoiadendron is derived from Sequoia and the Greek “dendron” meaning tree and giganteum meaning huge.

Think you would like to give these giants a try? Learn more about growing giant sequoias in your landscape and about growing them in containers.

What is a Native?

It occurs to me that some might stumble on this blog seeking an explanation of what we mean by native plants. The short answer is that most native plant groups in the United States define a native plant as one that was growing in the region prior to the arrival of European settlement.

This is different from a plant that is naturalized. We all are familiar with plants that we see growing wild along the roadside or in the woods or meadows of undeveloped land. However, many of these plants are, in fact, exotics that have escaped from garden cultivation. Before they were growing in the wild, some well meaning individual or nurseryman imported these plants to this country from other regions such as Europe (English Ivy), Asia (Privet and Kudzu), or Latin America (Sorrel also known as Oxalis).


In addition to plants that are found in wild areas, some native species have been cultivated to reinforce specific characteristics. Most often today, this is achieved through cloning of an especially attractive or hardy individual plant. While these plants are great for gardeners, they do not have the genetic diversity of wild plants. Whenever we select for particular characteristics whether through cloning or more traditional methods of breeding, we risk the possibility of also reinforcing negative characteristics that might remain recessive in a natural match. Such plants may be susceptible to a whole host of unanticipated problems. Temple Grandin provides some humorous and tragic examples of this in her book Animals in Translation.

Why does this matter?
Native plants have evolved over millennia in specific regions, and are a part of an interdependent ecosystem. Because of this they are uniquely adapted to that region’s climate (both temperature and rainfall), and the soils and geology. Other organisms in the region have also evolved to depend on these plants. Wildlife depends on specific fruits for food and specific insects have evolved to be able to pollinate particular plants.

One of the problems with imported or “exotic” plants is that a few have become highly invasive. Because they out compete the local native plants, they are altering the natural environment. The natural controls that would have kept these plants in check, such as disease and insects, are not present in their new environment. Continued use of these plants in gardens and planted landscapes, and the subsequent escape to wild areas, increases the risk to native flora and fauna. Look at the Georgia Exotic Pest Plant Council website for more information on this topic.

Benefits of Natives
If properly matched with site conditions, native plants will require very little maintenance, such as pruning, feeding, and protection with insecticides, fungicides, etc. Also, they are likely to be more drought and disease tolerant than many exotic plants. As mentioned, native plants provide a diverse and sometimes essential food and shelter for wildlife, and promote biodiversity.

Five Things You Can Do

• Learn about native plants and the natural communities where they grow
  
• Buy only nursery propagated plant material
  
• Don’t take native plants from wild areas unless the area is scheduled for destruction due to development, and you have the permission of the landowner
  
• Protect native plant and natural habitat areas
  
• Plant locally native plant species wherever possible

Sources for native plants in the Southeast from the Georgia Native Plant Society website.

CREATING YOUR GARDEN IN THE WOODS

When the developers of the Georgian Highlands asked Cynthia Hendry to landscape their Mountain Laurel Show Home, she intended to take a look but say no. She works almost exclusively in Big Canoe, another mountain community in North Georgia. However, the site and the vision of the developers – to create a nature preserve that sustains human habitat with little or no impact to the natural environment – caused her to reconsider. Ramesh Venugopal, the managing partner, is passionate about preserving the area. For him, “The year-round beauty of the Georgian Highlands is due, in large part, to its beautiful vistas adorned by native plants.”

Located at the gateway to the Southern Appalachians, the Georgian Highlands offers three to ten acre high-elevation home sites in a 3500-acre parcel surrounded by three national forests and thousands of acres of protected wilderness area. Jim Smith, a retired forester, tells us, “The deciduous hardwood forest has been undisturbed for many years, and the acidic soils of this pristine environment support a rich understory of smaller trees, shrubs, wildflowers, and herbaceous plants. Our goal is to create a community within a park rather than a park within a community.”

With this vision in mind, Cynthia was asked to create a landscape that would demonstrate the ideal, and serve as a sort of botanical garden of native plant ideas for new residents to use in designing their own landscapes.

The biggest challenge was an expanse of 30 feet from the back of the house’s two-story elevation to the forest edge of mature hardwoods. This area had to be completely cleared to build the septic field for the house. In addition, the slope of the site presented some unique demands. As I toured the site with Cynthia, Jim, and Ramesh, they explained some of the elements to consider when integrating a home site with the natural environment and trying to recover from construction.

1. Create windows through the trees. While clearing or topping trees can improve the view, these methods can have a negative impact on both the environment and privacy. In winter, leaves fall from the trees opening up views naturally. Minimal pruning can create windows to admire the view during other seasons of the year. A bonus is the changing view as new growth appears in the spring and frames the view with spectacular color in the fall.

2. Reuse all materials found onsite. Walk the entire site and identify plants to save. Look for perennials and ferns that can be transplanted – especially those that need division. The strategic placement of moss can make the garden appear more mature, and helps to blend the landscape into the surroundings. At Mountain Laurel, a spectacular stand of Carolina Silverbell trees near the house was carefully protected during construction. The few trees that had to be removed were turned into mulch. Thick topsoil was transferred from disturbed areas and used elsewhere.

3. Make a natural looking transition from house elevation to forest edge. Rather than grading, protect against erosion and navigate the natural slope with paths and structure. Cynthia made wide “S” curving paths that follow the contour lines of the property and create shallow descents. Stone smoothed by years of exposure was stacked in softly curving lines to retain the slopes. The big challenge was to select plant material that visually supported the architecture of the house and made the transition to the woodland. A few fast growing tall trees were needed in addition to understory trees, and shrubs. Because we have very few native evergreens suited to this elevation, Cynthia selected natives from elsewhere in the Southeast that she felt could adapt and thrive. For example, Bald Cypress Taxodium distichum is a highly adaptable, fast growing tree reaching to 70 feet with a narrow pyramidal habit. Even without a lawn, areas for relaxing should be included. Think about how the scene will evolve as the landscape matures to ensure trees and shrubs won’t block the view.

4. Match the right plant to the site. Consider plant and site conditions. For example, different plant communities thrive on dry, south facing slopes than appear on stream banks or cool, north facing slopes. Cynthia’s final design included 143 different species, so do choose a wide variety of plant materials. As you arrange the plants, think about how they grow naturally. Some tend to form dense colonies, while others are found widely dispersed. For more information on native plants, visit the the Georgia Native Plant Society website.

Most of all, don’t introduce exotic invasives that can actually harm the environment. Though Kudzu is not sold in nurseries, many of the most invasive plants can still be found in the nursery trade, including Chinese privet Ligustrum sinense and English Ivy Hedera helix. For more information on invasive pest plants, visit the Georgia Exotic Pest Plant Council website.

5. Bring the outdoors inside with the sound of water.
Cynthia built three long streambeds, which all emptied into a large pool with babbling waterfalls. Not a small undertaking, the 200 feet of streambed and pool areas used many tons of worn and moss-covered fieldstone from Tennessee and Arkansas.

6. Plan for low maintenance. Properly sited native plants withstand regional temperature and moisture extremes better than many exotics. By planting in the fall and early spring, plants become established before the stressful summer season, potentially avoiding the need for irrigation. Without a large expanse of grass lawn, mowing is eliminated. And, the use of a bog area as part of a natural filtration system can significantly reduce maintenance of ponds.
Hendry says, “While the landscape might look a bit contrived at first, as the plantings, mosses, and lichens grow and weather, the entire work will appear to be part of the forest.”

Cynthia Hendry owns Woodland Gardens in Big Canoe, GA and is well known for her extensive knowledge of Georgia natives. Donna Wright (Donna Wright Interiors) is also well known in Big Canoe and is an award winning nature photographer. Jim Smith works with the Georgian Highlands and others as a Native Plant Consultant and Registered Forester. He is also a past president of the Georgia Native Plant Society. More information on the Georgian Highlands can be found at The Georgian Highlands.

Photos courtesy Donna Wright and Jim Smith and Cynthia Hendry

This article was previously published in the March 2005 issue of Georgia Gardening Magazine