Sunday, September 8, 2013

The Cornelian cherry tree isn't a cherry tree






Species name: Cornus mas

Common name: Cornelian cherry

Location: Western University campus

I must admit, when I saw that this was part of the dogwood genus I was surprised...very surprised. But the more I examined the tree, the more it started to make sense. I'll explain more below. The Cornelian cherry is native to eastern Europe through parts of the Middle East (Iran, Armenia, Azerbaijan) and into parts of southwest Asia. Throughout many of these countries it is an important plant for traditional food and beverage production (more on that below), and at times even part of traditional medicine. There is no status official reported for this species, but since reports state that the products obtained from the plant are "better" from wild plants as opposed to cultivated plants, it is actively harvested in the wild. This probably contributes to a declining population, but a full evaluation on population size and reproductive ability would have to be done before any drastic conclusions could be made.

So why did it surprise me to find out this was in the dogwood genus (Cornus)? Well, I walk by this plant every day on my way into school and on my way home from school and I've always been convinced it was some kind of rose. Granted, I've never looked that closely. But it's a rose, darnit! Alas...it is not a rose. The leaves, for one, are absolutely characteristic of dogwood leaves. They are perfectly smooth on the top and bottom, as well as having "entire" margins (the margins of the leaves don't have teeth, unlike the fine, or sometimes large, teeth of members of the rose family) and very prominent main veins and secondary veins (and the tiny net-like branches of tertiary veins appearing to be completely absent at the base of the leaf). The leaves are also opposite on the stem, an important identification characteristic of the dogwood genus. The fruit also confused me; oval fruits with a pit inside them similar to a cherry pit but more almond-shaped is characteristic of the rose family, but can also happen in dogwoods (although much less common). The flowers, if I had of paid attention to them in the spring, is what would have also given them away. The tree produces bright yellow flowers (the flowers of the rose family are white, light pink or bright magenta) with only four petals instead of the rose family's five. The flowers are also produced VERY early in the spring (sometimes as early as February during mild winters, but most often the end of March), sometimes months before the first leaves start to appear. All-in-all definitely not a rose, and definitely a dogwood. The overall shape of the tree, although very difficult to discern from the first photo because of the buckthorns that are starting to re-grow (despite the massive clear-cut of buckthorn that occurred during the fall of the year before), is also characteristic of dogwoods and not roses. Without pruning, dogwoods often grow to a "triangle" shape, where the lower branches are very far-reaching and the branches above that become gradually shorter as the tree gets taller, so the canopy makes a cone-like shape. Rose family trees on the other hand are much rounder in shape, and all of the branches tend to reach upwards instead of outwards. Tree shape, if you can actually see the entire tree, is often a great characteristic to use to identify individual trees, but beware of pruning which can drastically alter the natural shape of the tree.

I eluded to some of the uses of this tree above, and I would be interested in trying some of the traditional beverages produced by this plant. After reading that the fruit was edible, I went back and tried one. Let me tell you: ripeness is everything for this plant. Oh, goodness. The fruits of this plant are somewhat unusual in that they only fully ripen after falling off the tree. I figured I could get close enough by finding a really red fruit on the tree and giving it a chew, but it was one of the most unpleasant experiences of my life. IT IS SO SOUR!!! I thought my cheeks were about to explode. Since I figured I had put my body through enough trauma I should just find a clean-ish fruit off the ground and give it a try. And you know what? Still sour. But not unpleasantly sour. Just not something you'd eat a bucket-full every day. Definitely not something I'd do again...I try to make a habit of not eating things off the ground. So, the berries are sort of edible but not very pleasant. What to do with them? Well, if you've ever walked under a Cornelian cherry tree about this time of year, you've noticed the smell: sickeningly sweet, and rotting fruit. Do you know what sickeningly sweet, rotting fruit is good for? Making alcohol. The starches in the fruit are already starting to break down by natural microbial action (which is why the fruit go from smelling like nothing to smelling like pure sugar in a matter of a few days), so if some brewer's yeast were to be added then you would get quite a potent alcohol produced. This idea has been exploited in almost every single country that this tree is native to; in Azerbaijan and Armenia the fruit are used to produce vodka, in Albania an alcoholic "moonshine" like beverage called raki is produced, and in Greece a liqueur is produced where the berries are fermented, then more are added back into the fermented liquid to impart flavour. Vodka doesn't usually have much flavour, but that's partly because of what you start with: corn, sorghum, wheat and potatoes don't have much flavour. Starting with a fruit that packs quite a punch I would think would give the vodka a truly unique flavour; I would definitely want to give it a taste-test compared to some "regular" vodka. I'm not so sure I'd be keen on raki, since I'm not a big fan of homemade hard liquor (I've tried chicha once, which is a South American version of moonshine made out of corn. The first few sips were OK, but very quickly became too much to handle for me flavour-wise, texture-wise, and the strength of the alcohol content). The Greek liqueur also sounds pretty tasty, so now I have a new thing to add to my list of "things to eat and drink in Greece" if I ever manage to make it there on vacation. Instead of fermenting the fruit, in Turkey and in Iran the fruits are pitted, dried and salted for a Craisin-like snack, which also sounds pretty good (it would be like a salty-sour raisin). In Turkey the fruits are also boiled with water and sugar to produce a thick syrup which is consumed with sparkling water as a beverage called a "Sharbat", and when poured over shaved ice you can see how we might get the English word: sherbert (or sorbet in France or sorbetto in Italy).

The fruit of the Cornelian cherry aren't just used as a food item or as a means of producing beverages; they're also used medicinally. The fruits themselves are exceedingly high in Vitamin C (only 3-4 berries would be enough to satisfy your daily requirement of Vitamin C intake) and so are often used as a means of warding off cold and flu in eastern Europe. Once the plant made it to China in the 1500s, the Chinese quickly started using the fruit of this plant in Traditional Chinese Medicine to restore kidney function, and to retain the body's essence. I'm not entirely sure what that involves, but if it involves the prevention of catching a cold (which involves sneezing a lot, an action often viewed as the "expulsion of the soul" which is why in English we say "bless you" afterwards) it's probably pretty effective. The wood has also been used as an important material in the construction of hunting tools, sporting equipment, machine parts, and the handles of woodworking tools. The wood is extremely dense, and actually sinks in water (which is incredibly unusual for wood). This makes it extremely durable, resistant to decay, and much stronger than other types of wood. The bark is also unusual; while it looks like "regular" bark, when it is boiled it gives off a bright red dye which was traditionally used to make the Fez hat. All that from a single plant!