The Deep Woods, Appalachian Gametophyte, and Ohio Geobotany

The Deep Woods

The Deep Woods of Hocking Hills and other parts of unglaciated Ohio are quite magnificent when most of what you are used to is flat farmlands! This eastern section of Ohio is known for its deep cavernous hills and caves, made up of sandstone. With this geologic history, it had produced a highly acidic environment that is home to some pretty special, specialized plants!

Chestnut Oak – Quercus montana

Chestnut Oak: This species looks quite a bit like the Chinquapin oak found in the limestone substrates of western Ohio, but its leaves differ in their callous tipped edges. The Chestnut oak lacks these callous tips and is considered to be more bluntly lobed, and also often wider. Its acorns (not chestnuts), are in favor of many avian and mammalian species such as wild turkey, songbirds, grouse, deer and other small mammals. While not used much today, the Chestnut oak bark has a very high tannin content that allowed it to be used for tanning leather. Lady Bird Johnson Wildflower Center (QUMO4)

Sourwood – Oxydendrum arboreum

Sourwood: Sourwood is specialized to acidic soils and is quite a treat to find. No literally, snap off a leaf and try one – they are quite delicious! Bees also find their flowers to be so sweet and tasty, and gourmet honey is made from those bees that can scope out this tree. Way back in the day, pioneers treated fevers by making a concoction with the sap; chewed on the bark to soothe mouth pains, and treated diarrhea, indigestion and dysentery with a tea made form the leaves. While we have modern medicines to relieve these nowadays, mountaineers still love to make tea with the leaves when they stumble upon this sweet sour plant. Arbor Day Foundation

Eastern Hemlock – Tsuga canadensis

Eastern Hemlock: This tree looks an awful lot like a Yew, but one way you can tell the difference is these two distinctive white bars on the undersides of the needle leaves. Eastern hemlocks are a good source of vitamin C and the needles are munched on by deer and rabbits. As for human uses. we typically use the lumber for paper pulp and newspapers! Lake Forest College

Ferns

Another key class of plants in the Deep Woods are the ferns. While we may think they all look the same, we can discover more about their Frond Type, Frond Dissection Type, and Indusium Type that will help us differentiate each species.

Maidenhair fern

Polypody Fern

Polypody: This fern is pinnatifid meaning the leaves are almost pinnate, but the sections don’t quite completely differ on the stalk. As for Frond Type, this fern is monomorphic with respect to its spore production. As for its indusium type, the sori are quite large and actually naked, meaning it lacks an indusium type altogether.

Christmas Fern

Appalachian Gametophyte

The Appalachian Gametophyte is a unique and remarkable as it has lost its sporophyte. While most ferns have that recognizable leafy frond, this species has lost that and produces entirely asexually through the remaining gametophyte you see above. Quite an evolutionary feat!

This asexual reproduction occurs via gemmae which lie along the margins of the gametophytes. They are much larger than spores, and a consequence of this is prohibiting dispersal that may have otherwise happened over longer distances. Therefore, these ferns travel very short distances through wind, water, or even animals like ants or even slugs (Kimmerer and Young). After dispersing they create independent, yet genetically identical clones nearby. We observed this as the Appalachian Gametophyte was relegated to small areas within the cave we were traversing.

One thing researchers have noticed is that areas that should be extremely suitable to the Appalachian Gametophyte have yet to be colonized by the species. The hypothesis on why this may be is because, as mentioned before, the fern lacks the ability to travel long distances, and therefore the current distribution of the species must have happened before the fern lost its companion, the sporophyte. Due to its current known distribution, it is believed that the ferns lost the sporophyte sometime during the last ice age.

While it was once believed that the Appalachian Gametophyte was a product of interspecies hybridization, that theory has been debunked. The current populations are not sustained by the long-distance dispersal of some tropical sporophyte as allozyme studies and the monphyly of the species indicate dispersal from the tropics only happened once in its history. Therefore, it can be assumed that the fern still had a fully functioning sporophyte in North America when temperatures were more favorable before its eventual extinction in the Pleistocene glaciations. Still, the Appalachian Gametophyte lives on through its gemmae, and minute dispersal.

Invasive Species: Barberry

Barberry: This grr-agh plant was introduced to the United States from Asia in the late 1800s as an ornamental plant. However, it quickly invaded forests, fields, and disturbed areas lending it to outcompete native plants and reduce biodiversity in those areas. It unfortunately also creates favorable habitat for ticks leading to an increasing risk of Lyme disease transmission. To control the spread, it is recommended one manually remove the plant and roots, apply herbicidal treatment to any roots or stumps left. Because of its extremely fecund and viable seeds, prescribed burns are also recommended to keep regrowth low and prevent more seeds from entering the seed bank. Commonwealth of Pennsylvania

A Tree in Trouble: American Chestnut

The American Chestnut was once a giant of the forest. Unfortunately, it is now in deep trouble as a fungus introduced from Asia in the early 1900s has wiped out and continues to wipe out American Chestnuts. This fungus causes wounds in the tree which eventually girdle it and disrupt the nutrient flow so much as to kill the tree entirely. While American Chestnuts can still be found, you will rarely find them to be much taller and wider than 10 years old.

The blight of the American Chestnut not only took away trees that were so big people could live in the bottom of them, it also took out key habitat, altering the ecosystem structure. Current efforts to mitigate the blight include genetic engineering of American Chestnut trees to make them more resistant, but most commonly hybridizing the tree with Chinese Chestnuts that are adapted to the blight. This has proved relatively successful, but is still considered a loss of the pure American Chestnut. USDA