SPIRAEA virginiana   Britt

virginia spiraea

Georgia<br>Perimeter<br>College Botanical Garden


By Thelma Glover

Deep below the rugged cliffs on the floor of Cloudland Canyon along the rocky, flood scoured banks of Bear Creek grows one of the crown jewels of Georgia’s rare and endangered plants, the incomparable Virginia spiraea. Anchored into cracks and crevices of sandstone boulders and rubble washed by the periodic flooding of the mountain waters, this rare southern Appalachian endemic endures the harsh conditions of a most difficult and precarious habitat belying any notion that it could ever make the transition to the dry, amended, red clay of the Piedmont to become the darling of the GPC Botanical Garden.

Federally listed in 1991 as a threatened plant this native spiraea species is presently found in only 24 sites in 6 states: Georgia, Kentucky, North Carolina, Tennessee, Virginia and West Virginia. All of these 24 colonies, with the exception of one located in Raleigh Co., West Virginia, share the same specific habitats along streams filled with bouldery rubble, periodically scoured by water, in deep craggy gorges or canyons similar to the two locations in Georgia.

The first collections of Virginia spiraea were made in the mountains of North Carolina in 1878. However, these were not identified as such until 1890 when Dr. Nathaniel Lord Britton described Virginia spiraea as a new species based on flowers and fruit collected along the Monongalia River in West Virginia. Ironically, this plant which bears the specific epithet ‘virginiana’ was not found in the state for which it was named until l985.

Of the two known sites in Georgia, both are on Lookout Mountain in the far northwestern counties of Dade and Walker located on the Cumberland Plateau. The population found in Walker County in 1898 is upstream from Lula Falls along Rock Creek on private property. The Cloudland Canyon site was discovered in 1948 in Dade County within the boundaries of the state park . To quote Tom Patrick, this site is “ at the head of a gulch or steep-sided, cliff-walled gorge, just before Bear Creek plunges down the west flank of Lookout Mountain ...accessible by taking a backcountry hiking trail, then bushwhacking downstream off the marked trail”. Those of us who have been to this site know that his description of its accessibility has been air-brushed.

The colony in Cloudland Canyon is recognized as uniquely different than the populations found elsewhere. (See description below.) From this colony a handful of stem cuttings were made by George Sanko while on a Bot Soc field trip (actually a perilous adventure) in June, 1993. From these cuttings, a beautiful garden worthy spiraea evolved which has no equal. Hundreds have since been propagated at the GPC Bot Garden in the last 6 years and sold at our plant sales or shared with nursery growers to be made available to the public.

Description: Virginia spiraea is a medium size colonial shrub from 3-10’ tall growing from slender, spreading rhizomes. Densely branching stems can be slightly to very arching. The leaves are deciduous, alternately arranged and very variable in size and shape, 1 l/2-6” long and 1 3/4-2” wide, ovate, elliptic to lanceolate, medium green on the upper surface and glaucous beneath. The leaf edges can be totally serrate, serrate only toward apex, or entire on the leaves on the upper most part of the shrub, or any combination thereof. The flowers are white to creamy white held in dense, tight, 2-l0” corymbs which begin blooming in the Atlanta area the first week of June.

The Cloudland Canyon colony of Virginia spiraea differs from the other populations by having larger leaves with no teeth and corymbs consisting of larger individual flowers.

In the past Virginia spiraea has been confused with Spiraea betulifolia since some of their characteristics overlap. In general, Spiraea virginiana is a larger shrub with longer leaves, a larger corymb and from all indications very site specific.

Cultivation: In view of Virginia spiraea’s natural habitat its hard to believe that it can thrive planted in regular garden soil in a backyard garden. But its true. Planted in full sun in loose rich soil amended with Nature’s Helper or its acid equivalent, this lovely shrub doesn’t seem to remember its origins. Plant it in late fall or winter after the leaves are gone. Give it the same amount of water given to any newly planted shrub or tree during initial establishment and cut back any weak stems to shape it. It blooms on new wood of the season so any cutting back or pruning should be done before spring. It grows very fast with or without fertilization but booming is fairly sparse when its young. Each season brings more blooms and by the third year the blooming is prolific. No pests, no diseases, no blackspot.

Propagation: According to literature on Virginia spiraea no seedling reproduction has ever been seen in the wild. Those few who have worked with collected seeds report very poor germination. Since it is colonial, root cuttings are no problem. We propagate by terminal stem cuttings in mid to late June. As with most members of the rose family, cuttings are easy and fast. It is a fast grower in a pot but the new growth is somewhat weak making it necessary to cut it back several times to encourage strong, upright growth.

Garden Use: Virginia spiraea planted alone or in small groups is the best thing going during the first part of June. Don’t use it in mass as you would the little dwarf Asian cultivars, its much too special. Planted in front of Emily Brunner Holly or bracted viburnum or any deep green, course, big leaf shrub will make the white flowers appear even brighter. Plant it where the flowers and sparkling protruding stamens can be enjoyed up close.

SOURCES:


Future:

Carolina Nurseries Lazy K Nursery Nurseries Caroliniana
739 Gaillard Road 705 Wright Road 22 Stephens Estate
Moncks Corner, SC 29461 Pine Mountain, Ga. 31922 N. Augusta, SC 29841
(800) 845-2065 (706) 663-4991 (803) 278-2336

Current:

Georgia Perimeter College Native Plant Botanical Garden
3251 Panthersville Road
Decatur, GA 30034
678-891-2668

REFERENCES:

Patrick, Thomas, James Allison & Gregory Krakow. Protected Plants of Georgia. Georgia DNR. Georgia Natural Heritage Program 1995

Glencoe, Jr., Joseph Francis, Spiraea Virginiana Britton: A Rare Southern Appalachian Endemic. Thesis Submitted for Degree of MS in the Faculty of the Graduate School of West Virginia University. Morgantown, West Virginia. 1961

Virginia Spiraea Recovery Plan (for) US Fish & Wildlife Service, Region 5, MA. Technical/Agency Draft. U.S. Fish and Wildlife Service, Region Five. Prepared by Douglas W. Ogle, Assoc. Prof. of Biology. Virginia Highlands Comm. College. December, l991. Abingdon, VA 24210

Final Status Survey Report: The Distribution And Abundance of Virginia Spiraea (Spiraea Virginiana). Submitted to U.S. Fish & Wildlife Service. Newton Corne, MA. by: Thomas J. Rawinski, Eastern Heritage Task Force. August 4, 1988. The Nature Conservancy. Boston, MA