The chestnut that horses don't want

Species name: Aesculus hippocastanum

Common name: horse chestnut

Location: Western University campus

The horse chestnut is a tree native to southern Europe around the Mediterranean and the Balkan Mountains. While the native range of this species is actually quite small, it is one of the dominant species that exists there and is also widely planted around the world. It can be a pretty nasty species (more on that below), but has a stunning flower display in late April and early May. The fruits, looking very similar to the fruits of the Ohio buckeye (which you can read all about HERE), start to appear in late summer. They are mostly left alone, but can be eaten (and seem to be enjoyed) by deer.

The common name of this plant is incredibly misleading, but is based in history. First the "horse" part refers to an anecdotal story that after horses ate the fruit, they would no longer complain of chest pain. You'd have to be some sort of pretty awesome horse-whisperer to be able to have a horse tell you it no longer had chest pain! The other minor detail to this story...you wouldn't be able to hear the horse telling you "Thanks! My chest pain is gone!" over the sounds of its seizures. Horse chestnut seeds and the fruit walls are poisonous to horses and should never be fed to them under any circumstances. Horses are pretty smart animals; they won't touch them. The other half of the name comes from the fact that it was believed that this tree was closely related to the American chestnut tree, mostly due to the fact that they have similar fruit and seed appearances. The leaves, however, are wildly different and the flowers of the true chestnut trees are also not nearly as showy. They are not easily confused, nor are they closely related! The true chestnuts and the horse chestnut are only distantly related.

The uses of the horse chestnut are so varied it makes me wonder if this really is a "miracle tree". The first use I'm just going to do the ultimate "thou shalt not do" and just copy-paste from the horse chestnut Wikipedia article because it's so mind-boggling. Here it is:
"In the past, horse-chestnut seeds were used in France and Switzerland for whitening hemp, flax, silk and wool. They contain a soapy juice, fit for washing of linens and stuffs, for milling of caps and stockings, etc., and for fulling of cloth. For this, 20 horse-chestnut seeds were sufficient for six litres of water. They were peeled then rasped, or dried and ground in a malt or other mill. The water must be soft, either rain or river water; hard well water will not work. The nuts are then steeped in cold water, which soon becomes frothy, as with soap, and then turns milky white. The liquid must be stirred well at first, and then, after standing to settle, strained or poured off clear. Linen washed in this liquid, and afterwards rinsed in clear running water, takes on an agreeable light sky-blue colour. It takes spots out of both linen and wool, and never damages or injures the cloth."
That is...crazy. How is this not marketed as a product?! A "natural" way to clean wool and linen, and the fibres are not destroyed in the process. The only thing I can figure is that it must be prepared fresh each time, and so it's viable today as a marketable product. If it was, it could be turned into a "Tide Stick type of product"--a Wool Stick?--and sold as a spot cleaner. This could be quite the money-maker...

The second historical use of the plant is as a soap and shampoo, along the same lines as the first use. The seeds are ground into boiling water in a sealable container (which sounds like a disaster waiting to happen, but what do I know?!), shaken vigorously (try not to have the container explode on you...), and then strained. Once the liquid is cool enough to be applied to the scalp, it works to remove the buildup from your hair. Nifty! Not nifty enough for me personally to want to try it, but nifty all the same.

Along a totally different vein, the seeds of the horse chestnut can also be broken into small pieces and then added to a fermentation solution containing the bacterium Clostridium acetobutylicum, from the same genus of bacteria that gives us botulism which is a very potent type of food poisoning, which produces acetone as an end product of fermentation (instead of the usual ethanol like brewer's yeast produces). Acetone can then be diluted to make nail polish remover, or it could be used later in the production of cordite (it's first use, prior to nail polish remover), an explosive used in bombs (and as a gunpowder replacement in other explosive devices like bullets).

And yet another completely different use, in order for an outdoor patio to be called a true "beer garden," it must be shaded by horse chestnuts according to Bavarian law. Now the term applies to any outdoor patio space where beer is the main item consumed, but that didn't used to be the case. Bavarian law also dictates (as an aside) the only four ingredients which may be used in the beer-making process: water, barley, hops, and yeast. If the "beer" that you drink contains anything other than those four ingredients (such as wheat beers, rice beers, or beers flavoured with things other than hops), it technically cannot be called beer.

One of the compounds found in horse chestnut seed extract, aescin, is used medicinally to treat a condition called chronic venous insufficiency or CVI. This condition arises when the veins can no longer return deoxygenated blood in your body back to your heart (where it pumps it to your lungs to push out the carbon dioxide and pick up new oxygen). This can result in severe pain due to a lack of oxygen in the extremities, and in especially severe cases can result in the loss of limbs. The causes of this condition can be quite varied, with specific medical conditions often arising in CVI (like diabetes, MS, and even a brief disruption of oxygen to a developing embryo in the womb) or the result of repeated leg injuries (like in the case of paratroopers, tree-climbers, mountain climbers, or people who climb utility poles for repairs). This is not a do-it-yourself medical treatment, however. The aescin must be carefully extracted from the seeds and purified in order to exclude any esculin, a deadly toxic glycoside also present in horse chestnut seeds, from the preparation. If even a small amount of esculin is ingested it can result in seizure, vomiting, severe dehydration, coma, and even death. Unfortunately, this doesn't stop homeopathic practitioners from prescribing it as a homeopathic remedy to thin the blood. Yet another example of the idea that just because it's natural doesn't mean it's good for you or even safe. Be aware of what you're putting in your body and the potential side effects!

The Buckeye Battle Cry revisited

Species name: Aesculus glabra

Common name: Ohio buckeye

Location: Western University campus

I know I've written a blog about the Ohio buckeye before (you can read my previous blog post HERE), but I wanted to blog about it again but with better pictures. And you know what? I'm allowed, because it's my blog :) So there!

The Ohio buckeye is a native species (well, marginally native. Definitely native to the northeastern United States; debatable whether or not it's native to southwestern Ontario) that does very well in full sun to partial shade. It's a medium-to-small tree in this part of Ontario because it's growing in a suboptimal part of its range, but further south into Ohio and Kentucky it can be a medium sized tree (up to 25 meters tall). The roots of these trees can tolerate intense rain and can tolerate temporary flooding, but do best in well-drained soil. There are some clear disadvantages to growing the Ohio buckeye as an ornamental species, and the first should be obvious: the fruit produced. If you're trying to increase the squirrel population, growing buckeyes in your yard is one of the best things you could possibly do. You don't want to come between a hungry squirrel and a buckeye tree! If, however, you have a lawnmower that you appreciate using and not replacing the blade every time you cut the lawn, you might want to reconsider this species. The fruits produced are enormous (in ideal conditions, some are almost the size of baseballs!), and when they split open they release one to three seeds. The seeds are large, hard, and really hurt when they hit you in the head. They do make fantastic ornaments, and are really stunning in flower arrangements. You can also collect the seeds and dry them to make beads, as is popular to do at Ohio State University. I can imagine they would be good for building neck muscles because they're so heavy, although I'm not sure why you would want to build your neck muscles.

Something that is often believed about the buckeye is that it produces inhibitory chemicals from the roots to prevent the growth of other species (called allelopathy) like in Norway maples and, to some extent, black walnuts. Fortunately, this isn't the case. To date there's no evidence that buckeyes produce allelopathic chemicals from their roots. Unfortunately, that doesn't mean that anything will grow under them! The canopy cover of buckeyes is just so dense that even shade-tolerant grass has a really hard time growing under buckeye trees. The best thing to plant under them would be highly shade tolerant ground cover, but even that might not do it in the long run. But the trade-off? Look at the trees! They're spectacular in their own right. They also turn bright orange early in the fall (late summer, really), long before other species start to change colour. And who doesn't love a bright orange tree in a sea of green?!

So how did the buckeye get to be so closely associated with Ohio? Well, there's the obvious reason that Ohio is the middle of the range for the buckeye, but that in its own right rarely causes a plant to be so ingrained in a state's culture. The story goes that Colonel Ebenezer Sproat arrived in what is now the United States in 1788 to command the Northwest Territory. Once he landed, the Indigenous peoples called Colonel Sproat "Hetuck" because they were so greatly impressed by him; he showed the native people immense respect and communicated with them instead of at them (as so many others did, and, to some extent, continue to do). To Indigenous North Americans, hetuck means the "eye of the buck" which shows power, respect and knowledge. I guess being called the eye of the buck is a great honour! He eventually became known as the "Big Buckeye" and all of the citizens under his control were his buckeyes. Eventually it became a term associated with all of those from and living in Ohio. The common name of the buckeye also stems from the fact that the seeds (or the "nuts") of the tree also resemble the eyes of deer. I bet you'll never look at a buckeye seed the same way again!

Should you decide to try to grow your own buckeye, make sure you find some nice plump seeds before they fall out of the fruit. They are very, very sensitive to drying and won't germinate if the seeds dry out too much. The best way to get around this is to find a fruit that has split open but has not yet dropped the seeds and take them home and put right in the ground. They won't germinate until the next spring, but there's usually a pretty good success rate. Plant a few, then pull all but a couple out of the ground in the summer. At the end of the next summer, choose your favourite and pull all of them but that one out (or leave a bunch! Nothing wrong with wanting a few buckeyes). Just keep in mind that you can't grow these indoors before transplanting (at least, not easily); they do require a period of exposure to extreme cold during the winter in order to germinate properly in the spring. Oh, and invest in a good rake ;)

The Buckeye Battle Cry

Species name: Aesculus glabra

Common name: Ohio buckeye

Location: Ontario

It should come as no surprise to find out that this tree is native to Ohio and the surrounding area. In fact, Ohioans are so attached to this tree it is not only the mascot of Ohio State University, but also the state tree. They've even gone as far as making an official state candy called the buckeye that mimics the tree's fruit. The "nativeness" of this plant is currently up for debate. Up until last year, I would have put the "non-native" status, but there was one stand of trees of Ohio buckeye discovered on Walpole Island in Ontario very recently. There has also been the suggestion that other individuals in Ontario might appear to have been planted but are actually free-growing. Either way, if these trees are native or not this is the northernmost extreme edge of the growing range.

The fruits of these plants are quite large and dangerous-looking due to their long spines. The seeds that the fruit contain are brown and very smooth, and are sometimes dried and used as beads for necklaces. The seeds contain tannic acid, which is one of the components of the process of tanning leather. These seeds are only one of many sources, and they were used for this purpose in the 1600s. The outer husk of the seed was also sometimes removed and the inner flesh boiled, mashed, then pan-fried in small patties. This food was called "hetuck"and was reported to be regularly eaten. I find this hard to believe, since it's actually rather well reported that the seeds of the Ohio buckeye tree are poisonous. Perhaps the method in which they were cooked denatured any biologically-active toxins.

Like humans, cows also show a severe sensitivity to chemicals in the buckeye seed, and so caution should be exerted before planting this species on a farm. Unfortunately, cows actually seem to be attracted to buckeye fruit so poisonings and death of livestock are routine occurrences in the fall when the plant sheds the seeds.