Deep Woods, the Appalachian Gametophyte, and Ohio Geobotany

 

Ohio Geobotany

Last week we visited the limestone substrate of western Ohio. This week, we visited Deep woods in Hocking County, located on the eastern side of the state. The substrate here is sandstone, which creates acidic soil. Below are three species that are characteristic of the area.

Sourwood (Oxydendrum arboreum)

Simple alternate finely serrated leaves, if you rip off a piece and try some, it actually tastes sour!

Fun fact: sourwood makes one of the most distinct honeys in the world.

Chestnut oak (Quercus montana)

Large alternately arranged leaves that are very shallowly lobed (less pointy than chinquapin)

Fun fact: Chestnut oaks are relatively more resistant to fire than other oaks! How cool

 

Hemlock (Tsuga canadensis)

Flat leaves with two distinct white stripes on the underside. They thrive in low wet environments.

Fun fact: They make horrible Christmas trees because the leaves fall off right after they die!

 

Ferns

Christmas fern

Hemidimorphic: fronds have fertile and sterile leaflets; sori on the leaflets toward the end

pinnate: leaf broken into leaflets that are separate

Polypody

Monomorphic: all fronds are completely fertile

pinnatifid: Divided into leaflets, but are not fully separated at the base

Cinnamon fern

Dimorphic: has separate fertile and sterile fronds

pinnate pinnatifid: Leaflets are fully separate, but sub-leaflets are not fully separated

 

Appalachian Gametophyte

Appalachian Gametophyte (Vittaria appalachiana)

A remarkable fern species that is very unique in its life stages. Unlike other ferns, the Appalachian gametophyte does not have a sporophyte stage. It only exists in its gametophyte stage. They reproduce asexually via the production of gemmae. These are larger and more costly to make than spores, which makes them harder to disperse large distances. They are dispersed via wind, water, and animals. A study done by Kimmer and Yound (1995) found slugs dispersing gemmae. This limitation in dispersal is also supported by its past and current range. It is absent north of the extent of the last glacial maximum, yet it is shown that they are able to survive there. Similarly areas in their range may be colonized, or be absent. This must mean that that used to exist in a sporophyte form to disperse initially and they subsequently devolved the sporophyte stage. It also is not likely that long-distance dispersal from a tropical sporophyte source is sustaining the Appalachian gametophyte based on allozyme studies conducted by Farrar (1990) and viewing its truncated range.

 

AHH INVASIVES

Japanese stiltgrass

This species originates in Asia and was brought into the US in 1919, where it was used to package porcelain in Tennessee. Now, it dominates much of the east coast. This pesky grass is very hard to control if you do not catch it early, as seeds can last up to 5 years in the seed bank. Mowing, herbicides, or hand pulling may be appropriate controls depending on the situation.

Source: https://ipm.cahnr.uconn.edu/invasive_plants_japanese_stiltgrass/#:~:text=Japanese%20stiltgrass%20is%20native%20to,Japan%2C%20Korea%2C%20and%20Malaysia.

 

Trees in Trouble

American chestnut (Castanea dentada)

While the tree pictured is not actually American chestnut, it is a Chinese relative. Anyways, the American chestnut used to be a tree that dominated eastern temperate forests. It was vital to the environment and early colonization. In the 1800’s, however, a blight was introduced from Asia. In a matter of half a century, chestnut populations were decimated, only leaving some saplings. This had a big impact on the ecosystem as chestnuts had ties to nearly every stage of the food chain. The American chestnut Foundation is doing work to try and develop a blight resistant chestnut tree through scientific research and breeding, with the end goal of restoring populations to their native range.

Source: https://tacf.org/history-american-chestnut/