Trees of Iuka Ravine

For our first field assignment, we were asked to use our phone cameras to explore our own neighborhoods. I am fortunate to live within a few blocks of a small park that is mostly maintained by members of the local community. It centers around a winding ravine bordered by old brick streets that break the city grid in a very pleasing manner. When it rains, a few inches of water collect at the bottom of the ravine, leading to a semi-riparian habitat that dries almost completely between rains. Previously I have seen skunk cabbage, salamanders, and other water-loving life forms in the ravine. But what sorts of trees might grow here?

Riparian corridor zones. Iuka Ravine’s steep slopes fill these zones up to Transitional. Image from USDA.

I must confess that although I have visited the ravine dozens of times, I never paid much attention to which species of trees it held (other than a few sycamores), preferring its wildlife and spring wildflowers (Bloodroot! Squirrel corn! Violets! Trillium!). I’ll admit: I was tree-blind. I was unsure whether I would be able to find enough different species of native trees that hadn’t already been covered in class, but of course, all my worry was for naught.

1. American Beech, Fagus grandifolia

Note alternately arranged twigs!

This image clearly shows this tree’s main identifying characteristics: broad leaves which are alternately arranged and simple. The leaves themselves display very distinct, straight parallel veins and toothed margins. According to Penn State’s site, the American Beech has shallow, wide-ranging roots which are excellent for “wet feet” conditions, like in the ravine. Another important characteristic is the tree’s smooth grey bark, which is pictured below:

Beech bark! This one looks unscathed so far.

Unfortunately, due to the qualities of the bark, trees in this genus are frequently mutilated by people who presumably want to leave their mark in something that’s going to live longer than they will. Penn State’s virtual nature trail chastises this behavior, as does practically every public park where beeches are found.

2. Ohio Buckeye, Aesculus glabra

Growth habit of a buckeye sapling

The Ohio buckeye is one of the few trees that everyone in Columbus probably knows, even if they aren’t interested in nature. The leaves are oppositely arranged and famously palmately compound, with very finely serrated margins and fine veins. (The horse-chestnut, which is in the same genus, has much heavier veins and deeper serrations).

I scraped a bit of bark off a young twig after learning from the Peterson Guide that you can distinguish between a Yellow buckeye and an Ohio one in this way, and it really does stink. I would probably compare it to fetid garbage. There was a large, dense stand of Ohio buckeyes in the ravine. The nut of the Ohio buckeye, though quite large and attractive, is one of the worst nuts to make nut butter out of because (as the Peterson guide points out) it is poisonous. This didn’t stop a few students my freshman year, who clearly hadn’t done their research. (Don’t worry, no one ate it.)

This specimen was vigorously attacked by hungry leaf miners.


3. American Basswood, Tilia americana

This tree is pretty small but I can still tell it has simple, alternately arranged leaves. As seen below, each leaf has a rough heart shape and serrate margins. Cute!

The Peterson guide tells me basswood is normally found on drier sites, so I’m curious how this one got here. This tree is also called Linden – a lovely name. The wood is quite soft and lightweight and is used for whittling/carving, beekeeping frames, guitars, and many other uses. In fact, basswood is so popular of a wood for carving that when I used a search engine to find sites, information about woodcarving came first in the results, before information about the tree itself!

I learned from an Iowa State U. site that its uses are not limited to carving. Basswood/Linden grows quickly and provides for many other species in its environment. Once it reaches a proper size it offers bountiful shade, and is often used for this purpose to shade young seedlings in nurseries. Its flowers feed many butterfly and moth species, rodents eat its seeds, and its low-density wood rots quickly, forming cavities in which birds and mammals nest. On top of that, it produces masses of fragrant, sticky blooms which are favored by bees. Basswood is truly one of the forest’s ecological MVPs!

4. Black Maple, Acer nigrum

Above, a display showing the tree’s opposite leaf arrangement and simple leaves. The bark of this tree was quite dark. And since it was a mature tree, it was was pretty tall as well! The bark’s color and texture was interesting to me, so I took a picture:

With a guest appearance by the Virginia creeper vine, Parthenocissus quinquefolia.

Winged “helicopters” (samara) are typical for the seeds of this genus, as is the many-pointed, lobed leaf shape. With three distinct lobes, smoother margins, and dense clusters of samara, I felt this tree was most likely to be a Black Maple. The Peterson guide rather ignominiously refers to the leaves and twigs of A. nigrum as “dull” and “drooping”, which was supported by my observation. This species produces sap that can be made into syrup, but not quite as much as does the Sugar Maple, to which it is so closely related that hybrids often form. Some sources say that the Black Maple should actually be considered a subspecies of the Sugar Maple. Ah, taxonomy is fickle.

5. Chokecherry, Prunus virginiana

This small sapling was found in the shade of larger maples. It has alternately arranged, simple leaves with a classic pointed oval shape. If you asked a child to draw a leaf, they would probably draw something similar to this. This together with the shape and size of the flower head (below) is enough to ID to species.

A closer look at the leaf reveals a finely serrated margin:

Chokecherries produce fruits that are extremely astringent because they are high in anthocyanins, natural antioxidants that most modern diets are lacking in. The Peterson guide attests that deer, game birds, bears, raccoons, and small mammals enjoy these fruits and also eat the twigs, as they do for the closely related Black Cherry. Chokecherry remains have been found at numerous archeological sites in North America and are one of the main ingredients in an important Native food: pemmican.

6. Pawpaw, Asimina triloba

This sapling intrigued me because it wasn’t leafing out in the same way as the others. It had long, smooth, mostly bare spindly branches with only a few leaves on the ends, along with what seemed to be a few oversized three-sided flowers in a deep maroon color. I was not able to identify it until I got back home because I had only seen older specimens. In retrospect, it makes sense to find it in the ravine because they favor riparian corridors. I hope this saplings grows big and makes lots of offshoots, because the Peterson guide says that’s how pawpaws spread and form groves! Their fruit is unusually large and delicious for a temperate forest tree, and they are actually a relative of more tropical genera like Annona (cherimoya).

Distinct three-sided maroon flowers are the reason for the specific epithet triloba.

7. White Oak, Quercus alba

Alternate, simple leaves and a distinctive… oak shape, with gently rounded lobes.

White oak is one of the most ecologically and historically significant trees in North America if not the world, often found in prestigious symbols and heraldry. Mature specimens can be over 450 years old and reach dimensions that even Wikipedia, with its famously strict neutrality, calls “magnificent”.

White oak acorns take only one year to mature to the red oak’s two, and are much less bitter. Like the chokecherry, they are used by Native Americans and are an important food source for many animals in North America: deer, bears, rabbits, turkey, squirrel, wood ducks and more. Because of how important it is to so many species, Q. alba is one of the defining members of the Eastern woodland. To humans, oak wood is the perfect material for barrels, ships, home interiors, and more due to a naturally water-resistant cellular structure. What a useful tree!

8. Shagbark Hickory, Carya ovata

This tree caught my attention with its weird banana-peel-like growths at the base of each young twig. It seems to have compound leaves arranged alternately, but that wasn’t enough to identify it. The peeling growths are quite distinctive, however. The namesake “shagbark” doesn’t form until the tree is mature.

From a University of Kentucky site I learned shagbark hickory is the most commonly grown hickory and truly “wild” populations are rare, even though its nuts are enjoyed by many creatures. What does this mean about the one I found – was it planted by humans? I also dug around on the National Wildlife Federation website and found that President Andrew Jackson enjoyed the moniker “Old Hickory” due to his toughness and ordered hickories to be planted around his tomb in recognition of this.

In the end…

Popkin’s NYT article got a lot of things right. I noticed a lot of the native species I was photographing didn’t have larger analogues nearby – no lines of osage oranges to mark fields or fence posts. Maybe these younger natives were planted by Iuka Ravine’s community volunteers, a concerted effort to increase native forest diversity. (A bit of research confirmed that such efforts are underway.)

People passing by while I was choosing trees seemed passively curious about what I was doing taking cell phone photos of leaves. I doubt they know the names of the trees that are shading them on their walk, protecting them from the city noise, filtering their air, and helping them feel that they’re in nature, escaping the confines of their homes – something we all need right now. But those folks don’t need to know which tree species are best for building homes or fences or which ones are poisonous to cattle. If they are to care for the trees, it will be for an emotional reason, not a practical one.