My wife and I just got back from a visit to Buffalo National River in Arkansas. It is a beautiful place to see nature at work. We stayed in an old hotel in Harrison, and planned our days in such a way that we could work around the intermittent and unpredictable rains. (I recommend the 1929 Hotel Seville in Harrison as a place that is close to the river but inexpensively elegant in case you have to sit around in the lobby during rain.) We did all of our hiking between rains on May 28. One of the main attractions of Buffalo National River is the green forests—which you cannot have without lots of rain.
Canoeists and kayakers revere the Buffalo National River for its scenic limestone cliffs:
But to an evolutionary ecologist, the river is also a living system. Along the river itself we saw lots of seedlings and re-sprouted saplings of box elder, sycamore, sweetgum, catalpa, birch, and persimmon. I do not know why, but we saw not a single cottonwood. These trees grow in areas disturbed by strong floods. If they get a chance, they grow into forests, at least the boxelders, sycamores, and sweetgums; the catalpas do not live long enough to become canopy trees, and the persimmons spread horizontally by underground stems rather than upward to reach the canopy. In a floodplain forest long undisturbed by floods, we saw very large birches and sweetgums, along with southern red oaks. This photo is of a very tall birch, but it was still leaning halfway over the way it did when it was a riverside sapling.
When we hiked along Mill Creek, we saw some floodplain forests that were almost monospecific stands of box elder:
The riverside forests and the bluff forests were very different. Some species, such as sweetgum, grew in both; but the bluff forests had no box elders. On a bluff, we saw at least one tree species that seemed out of place: a chittamwood tree, which I associate with drier forests. The bluff presumably provided an ecological refuge for this tree, which would not be able to compete with the tall oaks (white, northern red, southern red, and chinkapin) and hickories. Some trees such as pawpaw specialized on open spots on the forest floor. Mesic forests and drier forests have different conditions and different dominant tree species; but because of dry microenvironments, trees more common in drier forests can find a foothold in these mesic forests—this is one reason that mesic forests have such high biodiversity. (We did not, however, see any post oaks.) We recognized 42 flowering plant families; there must have been more. (It’s nice to have a spouse who, though not a professional botanist, loves plant families as much as I do.)
To accommodate search engines that may search for information about these trees, I will list some of the Latin names. Those of you who are not interested in Latin names, please skip to the next paragraph.
Acer negundo (Aceraceae), box elder
Asimina triloba (Annonaceae), pawpaw
Betula nigra (Betulaceae), birch
Catalpa bignonioides (Bignoniaceae), catalpa
Diospyros virginiana (Ebenaceae), persimmon
Liquidambar styraciflua (Altiginaceae), sweetgum
Platanus occidentalis (Platanaceae), sycamore
Quercus alba (Fagaceae), white oak
Quercus falcata (Fagaceae), southern red oak
Quercus muhlenbergii (Fagaceae), chinkapin oak
Quercus rubra (Fagaceae), northern red oak
Sideroxylon lanuginosa (Sapotaceae), chittamwood
We saw more than just plants, of course. It was also the perfect day for this beautiful species of fungus:
On the rainy day we visited Mystic Caverns, which are very beautiful:
And delicate: the oil from even one finger-touch can disrupt mineral deposition. Some of the stalagmites resembled Schmoos from an Al Capp cartoon; in fact these caverns used to be owned and operated by Dogpatch USA, a now bankrupt and vine-engulfed amusement park right across the highway.
The leader was a preacher and handgun instructor who preached us his guns and creationism gospel. He pointed out, quite correctly, that calcite deposits can form quickly; he should know, as he has watched them form. But he also showed us a limestone rock with crinoids in it, and claimed that they could only have come from The Great Flood. He did not consider the possibility that the crinoids were in the limestone parent material upon and around which the calcite deposits formed. I did not ask him any of a thousand possible questions. What would have been the point? Besides, I was the guy who belted out “Deep River,” an old gospel song, in the echo chamber (at the manager’s invitation). This was where the orchestra used to stand in the 1930s when this cavern had a moonshine still in the back and a dance floor. (Presumably some of the people, drinking moonshine, thought they were dancing until somebody stepped on their hands.) I chose to sing Deep River rather than to argue against a creationist. I was, after all, on vacation. Most of the people on the tour were what Mark Twain called Arkansaurians and would not have believed me; the others were young people, including a Japanese couple, who got rained out of their rock climbing plans and presumably already agreed with me. So this was not what one would call a teachable moment.
The Buffalo National River is a beautiful place to visit and to observe the natural world closely.