Spring is the season of blooming in the Fern Valley woodland area. April begins the blooming season with the wonderful, yet subtle, spring ephemerals and other early wildflowers. Spring-beauty (Claytonia americana), Round-lobed hepatica (Hepatica americana), and Oconee bells (Shortia galacifolia) are no taller than six inches, but they are very early and lovely in their form and flowers.
While the weather is warming up and the days are rapidly growing longer, the spring ephemerals rush to bloom - be pollinated - and produce seed, while converting sunlight into plant growth, all before the leaves on the trees come out and shade the woodland floor. Then the ephemerals quickly go dormant, their leaves fading away and seeds scattered by industrious ants.
The month of May brings into bloom a more colorful palate of woodland phlox, native azalea, and a number of the Trillium species, including Trillium discolor, T. catesbei, and T. cernuum. With the shade of the closed canopy, the woodland falls under the prominance of the non-flowering ferns. This is when the meadow and prairie plants burst into their June extravaganza of bloom that continues on into the summer.
An odd sight in Fern Valley is the late-fall leaf removal. “It’s a native plant garden, why mess with nature?” some ask. Oddly enough we began removing leaves in autumn in order to expose small tunneling rodents to predators such as fox and owls. Our plantings were apparently being devastated by voles. Our shrubs were regularly losing healthy branches and were simply being unearthed by tunnels. Not only was the vole damage reduced in the areas where we removed leaves, we also observed a great improvement in the growth of many wildflowers including, trillium and phlox, and with all our spring ephemerals including the the spring beauties, trout-lilies and toothworts. Leaves were always returned to the plantings after a few weeks of exposure. But the returned leaves were shredded, which lead us to the following conclusion.
Because the majority of leaves that fall in Fern Valley are either from American Beech (Fagus grandiflora) or Oak trees (Quercus spp.), the growth of many wildflowers was suppressed by their thick, slow-to-decompose leaf litter. Fern Valley displays a denser array of wildflowers and shrubs than you would encounter in many natural oak beech woodlands. In order to maintain the varied growth we need, we improve the growing conditions for the wildflowers and ferns by processing the leaves, and returning them to the area in winter. All the areas from which leaves are removed are eventually covered with shredded leaves, a wonderful soil enhancing mulch.
The oldest tree in Fern Valley is probably about 240 years old. We have determined this by counting the annual rings on trees that have been blown over in a few severe storms. Hurricane Isabel in 2004 brought down a perfectly healthy, but very lopsided white oak near the Fern Valley pond. This tree still lies across the path near the Fern Valley pond, where you can count its 230 annual rings. There are a few additional oaks in Fern Valley that seem to be the same age as that fallen giant, like another tree that fell a few years earlier and had an annual ring count of 240. Both of these trees grew near the Fern Valley stream, protected from being cut to make way for farming that took place on much of the arboretum grounds.
We grow a small number of orchids in Fern Valley. Unfortunately many native orchids are difficult to establish in gardens, and even in natural areas where they don’t grow already. There is no evidence that Fern Valley was ever home to such beautiful orchids as the pink ladyslipper or showy orchis. And our efforts to establish them have not yet met with success. We do have small plantings of yellow ladyslippers and cranefly orchids along the north trail in the piedmont section of the garden.
North American orchids haven’t been grown much by the nursery industry, until recently. This means that orchids grown in gardens were often collected directly from the wild. This wild-digging is very destructive, degrading natural areas and creating footholds for weed infestations. It is only very recently that native orchids are being grown through advances in our understanding of their reproductive biology. There is no clearinghouse of information for nursery propagated orchids, but the Internet can provide a wealth of information on nursery propagated orchids for specific areas of the country.
Another way to see orchids is in their natural environment. Your state's native plant society can guide you to areas where you can enjoy seeing orchids in the wild, growing in their natural habitats. That is probably the most satisfying way to see our native orchids – in nature!
We allow a lot of jewelweed Impatiens capensis to grow in Fern Valley because of its importance to hummingbirds. Jewelweed produces nectar-rich orange flowers in the midst of the summer providing hummingbirds with important nutrition. Jewelweed is an annual and produces a profusion of seedlings. Each year we leave small groves of jewelweed for the hummingbirds who have an easier time finding large clusters of plants than they do finding individual plants.
There are wildlife enthusiasts who are willing to encourage the growth of poison-ivy (Toxicodendron radicans), but it's a rare gardener who wants it around. About nine out of 10 gardeners (as in the general population) are allergic to poison-ivy’s rash-causing oil, urushiol. The oil is present in all the plant’s parts including the leaves, stems, and fruits. In areas where poison-ivy grows freely, it is difficult to manage other plants due to the problems caused by contact with the ivy. Bird-lovers, however, value the plant’s ability to produce nutritious fruit for birds. Small white berries are borne on mature stems that can be found growing up tree trunks or taking a shrubby form on the ground. Large poison-ivy plants are pretty much removed from Fern Valley, but a small labeled plant is usually maintained, as there is now just down the main path from the garden shed.
Fern Valley is a great place to observe nature, not collect from it. As it is stated in the arboretum’s official rules, “All plants, fish, and wildlife are protected.” Nothing should be removed from the arboretum except new knowledge, good memories, and maybe a few great photos!
Beneath the dense shade our American beech, oaks, and tulip trees, we find that Christmas fern Polystichum acrostichoides, broad beech fern Phegopteris hexagonoptera, white wood aster Eurybia divaricata and plantain-leaf sedge Carex plantaginea grow very well. But keep in mind that in natural woodlands that are dry and shady the most abundant “ground cover” is usually leaf litter.
Damp shade is a wonderful opportunity! We grow beautiful ferns, wildflowers and shrubs in a section of Fern Valley that is low-lying and adjacent to our stream. Depending on what region of the country you are from will determine which natives do well in you area, but a short list of the plants that flourish in our shady, poorly drained site includes:
We continue to look for a good location to grow Franklinia at the arboretum. Unfortunately, we have determined a number of locations that have not been suitable. As of April 2006 there are two Franklinia alatamaha plants on the gounds. One is located just south of the National Capitol Columns facing the Fern Valley prairie planting, and the other is on the south side of Beech Spring Pond, near the bridge over Hickey Run.
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Last Updated March 6, 2006 3:13 PM
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