Most of the buckeyes in the arboretum are what we call 'red buckeyes.' In some of the older literature from the first half of the 20th century, you will also find the names 'scarlet buckeye' and even 'flame buckeye' used to refer to this plant.
There is one specimen, however, who is a bit different. We've covered this tree in a previous post. It can be found just up the path near the small parking lot between the Student Union Building and Hamilton Hall.
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| We currently have it tagged as Scarlet Buckeye under Aesculus splendens. Due to the current taxonomic situation, this is as good as anything else we might use, although unfortunately not definitive. |
Is it a different subspecies? Or perhaps just a local variation of little consequence? This is very hard to say because today people are not much interested in our native buckeyes. To find some clues, let's dig into the literature.
Correspondance between Charles Sprague Sargent (1841-1927; a Harvard botanist who operated the Arnold Arboretum) and Reginald Wodehouse Somers Cocks (1863-1926; professor of botany at LSU and Tulane) contained in the Journal of the Arnold Arboretum (volume 46, 1965) contains references to Aesculus pavia, Aesculus splendens, Aesculus discolor var. mollis. These scientists of the early 20th century did not consider these to be synonyms; they used those names to describe different buckeyes growing in Louisiana and the surrounding states. Today, all of this has been collapsed into Aesculus pavia.
The fruits of the scarlet buckeye and red buckeye differ appreciably. The former is bumpy or warty, while the latter lacks those noticeable bumps. Below, we have pictures of the scarlet buckeye. For comparison, you can find pictures of the red buckeye fruits here and here.
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| This fruit capsule hangs from the scarlet buckeye, photographed today, October 17, 2021. Note the black dots, which mark the bumpy texture. Only two capsules were seen hanging from this tree. Sections of another capsule were found in the leaf litter. All three capsules have bumps marked with black dots. |
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| Seen from below with proper lighting, the extra texture on these fruits is quite distinctive. |
In the arboretum, our red buckeyes produce large numbers of fruits. For instance, two years ago we had a large crop, which you can read about here, and this year, we are seeing the same red buckeye trees full of fruit capsules, some of which have started to split. By contrast, our scarlet buckeye rarely produces fruit.
Are these differences a subspecies variation or a result of competition? The scarlet buckeye has a peppervine close at hand, which may be stealing its resources. We chop back the peppervine every couple of years, just to make sure the scarlet buckeye isn't overwhelmed. The vine always bounces back quickly.
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| As you can see in this photo, the peppervine (Ampelopsis arborea) has thoroughly attached itself to our buckeye. We allow this, although we stipulate a pruning regimen. |
Another complication is its flowers, seen here. Yellow flowers are characteristic of the Ohio buckeye (Aesculus glabra.) Maybe we have a mutation, a hybrid, or an undescribed subspecies. Let's keep an eye on this specimen.
