1. Overview of This Web Site

Between March and August, 1951, Henry T. Skinner drove 25,000 miles through the southeastern and eastern United States searching for native azaleas. From this field survey, approximately 8,000 herbarium specimens and 500 living plants were sent to the Morris Arboretum of the University of Pennsylvania in Philadelphia. Dr. Skinner's journey deserves to be called one of the great plant explorations of the U.S. Fifty years later, his discoveries are still influencing American horticulture.

During his travels, Dr. Skinner kept notes and lists of the azaleas he found in a two-volume Southern Collecting Trip Record Book that is now part of the Henry Thomas Skinner Papers in the Special Collections Department of the University of Virginia (Accession Number 10553-ad, Box 10). Dr. Skinner also prepared daily Notes of Southern Collecting Trip Routes (Accession No. 10553-ad, Box 10). A year after his trip in August, 1952, he made a list of the 500 plants he had sent back to the Morris Arboretum; this list is entitled "Native Azaleas" (Accession No. 10553-ad, Box 7, Folder "Native Azaleas, 1935-1955").This Web site includes images of the handwritten Record Book and Notes of Routes, with transcriptions, and images of the list of the Native Azaleas.

Many of the herbarium specimens that Dr. Skinner collected are still available at the Morris Arboretum. The Arboretum also has a list of the specimens. Even after 50 years some of the plants sent back to the Arboretum are still alive.

Dr. Skinner also kept an expense book that is in the Special Collections Department (Accession Number 10553-ad, Box 10), but it is not digitized. A note about the expense book is at the end of this introduction.

Four years after the 1951 trip, Dr. Skinner published a famous article entitled "In Search of Native Azaleas," in the Morris Arboretum Bulletin, Volume 6, numbers 1 and 2, 1955, pages 3-10 and 15-22. A transcription of this article is also included at this site.

The article provides a good overview of Dr. Skinner's explorations. The Record Book and Notes of Routes provide the day-to-day detailed record in the field of what Dr. Skinner was discovering in 1951.

The transcriptions of the Record Book, Notes of Routes, and Morris Arboretum Bulletin article can be searched by using the search page of this site. The search allows you to find all instances in the transcriptions of given words or abbreviations.

The site also contains some recent photographs of the various species of native azaleas. These photographs were taken in the southeastern U.S. in areas visited fifty years ago by Dr. Skinner. There are also some photographs of the famous stands of azaleas at Gregory Bald in North Carolina-Tennessee and at Wayah Bald in North Carolina.

2. Brief Biography of Dr. Skinner

Dr. Henry Thomas Skinner was born in England in 1907 and died in the U.S. in 1984. He was married to Anna M. Wood. He studied at the Wisley School of the Royal Horticulural Society, then came to the U.S. in 1927, where he obtained a B.Sc. from Cornell University in 1936; M.S. from the University of Pennsylvania in 1938; and Ph.D. from Pennsylvania in 1952. He was curator of the Morris Arboretum from 1940-1943 and from 1945-1952, his work there having been interrupted by service in the USAAF in World War II from 1943-1945.He was director of the U.S. National Arboretum in Washington, D.C. from 1952-1973.

Dr. Skinner served the plant community in many ways through work and committees during his lifetime, a prime example of this being his development of the U.S.D.A. Hardiness Zone Map. He served as president of several plant organizations including the American Association of Botanic Gardens and Arboreta (1947), American Horticultural Society (1962-63), and vice president of the Royal Horticultural Society (1973-1984). He was the recipient of numerous awards, including the prestigious Arthur Hoyt Scott Horticultural Medal (1963); Gold Medal, American Rhododendron Society (1965); Liberty Hyde Bailey Medal, American Horticultural Society (1972); Gold Medal, Massachusetts Horticultural Society (1973); and the Royal Horticultural Society’s Veitch Medal was presented to R.W. Skinner, a nephew, on behalf of Dr. Skinner (1983).

3. Using This Web Site

When you click on "Documents of Southern Collecting Trip," you get a list of months for the Record Books and the Notes of Routes. Click on one of the months, and you'll get images of Henry Skinner's handwritten pages from the books, side-by-side with transcriptions of the handwriting. Depending on the speed of your connection to the Internet, a month's page images can take some time to load. Once the images have loaded, if all of them do not display as you scroll through the month, try refreshing or reloading the page.

To enlarge a page image for a particular day, click on it. Depending on the settings of your Web browser, an enlarged image will open in a new window, or you may have to click again on the new image to enlarge the view.

In Internet Explorer, for example, your Internet Options may include Automatic Image Resizing. When you click on a page image in a month's collection of images, you get an image that fits the size of your screen. Put your cursor in the lower right corner of the resized image, and an icon will appear that you can click on to zoom in on the image. Further information is available at www.microsoft.com by searching for "automatic image resizing."

4. Explanation of Dr. Skinner's Notebooks and List

Dr. Skinner used many abbreviations and codes in his notebooks. When describing the plant specimens he collected, he used the usual metric abbreviations such as mm (millimeter) for describing the flower diameter and m (meter) for describing the height and/or width of the plant.

The entries describing flower color are mainly from A Dictionary of Color by A. Maerz and M. Rea Paul (New York: McGraw-Hill, 1950). The Maerz and Paul color code consists of a number, a letter, and another number as illustrated in this entry from Dr. Skinner's Record Book:

"Diameter 30 millimeters. Lobe pale pink—1D1. Darker tube 1H3. Height 2 meters"

The entry indicates that the flower diameter is 30 millimeters, the limb or expanded part of the petal in a gamopetallous (joined) corolla is the pale pink of the color patch 1D1 in the Maerz and Paul book. The flower tube (joined part of the corolla) is the darker pink of the color patch 1H3 in the Maerz and Paul book. As a general guide, Maerz and Paul codes beginning with 1-4 (for example, 1H3, 2F10, 3K9) indicate pink to red to reddish-orange colors.Codes beginning with 9-10 refer to yellow to orange, and codes beginning with 42-50 are blue to pinkish-red to purple.

In a few places Dr. Skinner used the Horticultural Colour Chart (London: The British Colour Council in collaboration with The Royal Horticultural Society, 1938, 1940).

“Bushes 2—3˝ meters. Colors: (a) Limb Mandarin Red 17/1 Tube = little darker, (b) Brick Red 016, (c) Mandarin Red 17/2about same, (d) Poppy Red 16/1 tube usually darker.”

The HCC color names are usually given along with the patch or sheet numbers so these entries are more self explanatory than the Maerz and Paul colors. In this entry Dr. Skinner is describing the flowers of four plants, a-d. Mandarin Red 17/1 would mean one let-down with white from the full color while Mandarin Red 17/2 would mean a second let-down with white from the full color. (“Let-down” with white refers to tint and is a mixture of white pigment or paint with a chromatic pigment or paint. This contrasts with “shade” which is a mixture of black with a chromatic.) Sheet 16 is Poppy Red. Other numbers used are 018 for Jasper Red and 18 for Vermillion.

In Dr. Skinner's August, 1952 list of the 500 plants that he sent back to the Morris Arboretum from his Southeastern trip, the columns labeled "HTS#" (Henry T. Skinner number) refer to the paragraph numbers in the Record Book. "Arb. #" is the Morris Arboretum accession number. The table of species names in the next section of this Introduction can be used to interpret the abbreviations in the columns labeled "Name." As an example, paragraph 15 in the Record Book for March 22 is as follows:

"15P. Deep pink W28. Deep tube. Good pink limb."

From the Native Azaleas list we can see that HTS# 15 is a plant of Rhododendron canescens from Florida, and in August, 1952, it was in Good condition at the Morris Arboretum.

5. Native Azaleas

The southeastern U.S. is blessed with various species of native azaleas that extend from the Coastal Plain, to the Piedmont, the mountain and valley ranges, and the Appalachian and Ozark Plateaus. Native azaleas can still be found today in many of the areas that Dr. Skinner visited in 1951. Other locations where he collected azaleas have not been so fortunate and the azaleas have given way to wider highways, larger towns, cities, and housing developments,

Some azaleas surveyed by Skinner were and still are in protected areas owned by the federal or state governments. Gregory Bald is in the Great Smoky Mountains National Park and is protected by the National Park Service. The bald area has had encroachment by the forest, but the National Park Service has been trying to maintain the open area for the azaleas. Wayah Bald in the Nantahala National Forest in North Carolina is also protected, but there is very little bald area on Wayah anymore, and with so much shade the spectacular mix that Skinner found is not as evident, although there are fine species of R. arborescens and R. calendulaceum and a few hybrids there. Cowee Bald still has a few calendulaceum, but now also has many high tech towers on it of various kinds.

K. A. Kron in her seminal 1993 publication "Revision of Rhododendron Section Pentanthera" (Edinb.J.Bot.50(3): 249-364) lists 15 species of deciduous azaleas, only 12 of which are found in the eastern part of the U.S. (Rhododendron luteum and R. molle are not native to the U.S. and R. occidentale is found on the west coast of the U.S.) Since that time Kron has also published one new species of deciduous azaleas for the East, R. eastmanii.Two other species of native azaleas are in the eastern U.S., R. vaseyi and R. canadense, but they are in Section Rhodora, not Section Pentanthera, and were not noted in Dr. Skinner's work. Names of some of the species Skinner studied have since been changed and some species subsumed into other species. The following table displays the names used by Dr. Skinner and those used by Dr. Kron.

Dr. Skinner found swarms of hybrids between two or even three species of native azaleas in many places and commented on them in his notes. (A swarm is an extremely variable population derived from the hybridization of at least two different taxa, which occurs where the range of inter-fertile species overlap.) These swarms were often notable for the beautiful colors that appeared in them when the azaleas hybridized.

Gardeners and landscapers are using more native azaleas in home landscapes today with the trend towards gardening with native plants. With the large number of species and hybrids available there should be plants available for many types of locations. Many of the species of native azaleas do well at the edge of woodland where they get partial shade but also enough sunlight to bloom well. In deeper shade the plants do not bloom as well even though they may survive. Cultural instructions for rhododendrons can be found at the American Rhododendron Society.

Lists of nurseries that sell native azaleas are maintained by the American Rhododendron Society and the Azalea Society of America.

Botanical and other public gardens that have collections of native azaleas include, Callaway Gardens, Pine Mountain, Georgia; the State Botanical Garden of Georgia, Athens, Georgia; Biltmore Estate, Asheville, N.C.; North Carolina Arboretum, Asheville, N.C.; Charlotte Botanical Gardens, University of North Carolina, Charlotte, N.C.; and Norfolk Botanical Gardens, Norfolk, Virginia. Some of the plants sent back to the Morris Arboretum by Dr. Skinner are still living at the Arboretum in Philadelphia.

More information about native azaleas is available through the Species Study Group of the Middle Atlantic Chapter of the American Rhododendron Society. An excellent Web site affiliated with this Study Group is "East Coast Native Azaleas," with additional information at "Native Plants and Wildflowers." In addition to the Middle Atlantic Chapter, a few other regional chapters of the American Rhododendron Society may also have study groups. The Azalea Society of America also has many members interested in the native species.

6. Note on Dr. Skinner's Expense Book

During his 1951 trip Dr. Skinner kept a detailed record of what he spent each day from March through August. The Expense Book is entitled "Southern Collecting Trip Expense Book." For the entire period there are usually only 4 entries each day. May 14 is typical. The 4 entries, with costs in dollars, are:

Breakfast [plus]
Lunch 1.20
Supper 1.05
Cabin 4.00

The exceptions to the 4-item expenses are things like

May 8: Brake adjustment 1.00
May 10: Tip to farmer for finding plants 1.00
May 27: Fix flat 1.25

The other class of additional expenses is for mailing plants. Some examples:

May 29: Express-plants 2.43
July 9: Express chgs-Knoxville 2.98
July 17:Express-plants 4.22

For the July 17 shipment of plants (and for some of the other shipments) there is confirmation in the Notes of Routes. July 17 is particularly interesting. Here's what the Notes of Routes says:

"Another very hot day & not too much progress - chiefly because the entire morning was spent in packing a fairly large batch of plants & in taking these to Ozark, the only fringe beetle free shipping point in all of this part of Alabama. Also mailed films for development."

At the end of the expense book Skinner summarizes his costs:

Total mileage: 24,676 miles
meals and lodging: $880.54
gas: $412.00
total: $1,292.54*

*The total does not include costs of film and developing.