Some of my best botany field trips have been to supermarkets and produce stands.
There’s always something interesting to see, and it makes an easy way of bringing classroom botany close to home – and the kitchen. Now, I’ve never taken one of my classes to a European city for a late-year visit to one of the famous farmers or Christmas-time markets, but I bet it would be fun. In Vienna, the big city market is the place to be for produce. For a while now, and even beyond the Christmas season, one can see crates of this odd fruit for sale. It is sold as something of a confection. It is probably not quite as popular a seasonal treat as it was a few decades ago, but it remains a charming curiosity that is fun to play around with. These pods are indeed beans, the fruits of a red flowered, evergreen tree that is native to the Middle East, well into Turkey and Saudi Arabia. It has been known and used since the time of the Egyptian pharaohs and was spread around by the Greeks. The Romans were fond of it, too. Pods have been recovered from the ruins of Pompeii. This drought-resistant species is now cultivated as far west as Spain and is grown in a few places in the Southern United States. The shiny, purplebrown fruits are elongated and flat, but they tend to curl, somewhat resembling a goat’s horn. The scientific name comes from a Greek word which means horn. The beans have been used for thousands of years as a fodder for cattle and goats. Each pod contains a dozen or so seeds, which are surrounded by a sweet, edible pulp.
This pulp is quite fragrant – pleasantly – and provides a chewy, although a bit messy, snack. Mixed with chicory, the pulp makes a coffee substitute, but its most important use by far is as an excellent chocolate substitute. The seeds themselves are useful, too, providing an important gum source, which is used in food additives, cosmetics, adhesives and as a binding component of match heads. As a member of the legume family, this plant is related to various species known as locusts. One of the common locusts of Eastern North America is honey locust, previously a thorny subject for this column and a species which also has elongated, flat, curling pods. But back to the marketplace in Vienna. The German name for our mystery plant is johannisbrot, which means John’s bread, a direct allusion to the bible story of John the Baptist. Roaming around in the wilderness, there weren’t many fast-food joints to visit, so he would have had to do what he could, perhaps subsisting, as they say, on locusts. There is considerable controversy as to whether he would have been eating the insects or the pods of this tree, which would have been on hand.
[Answer: Carob • Ceratonia siliqua]
John Nelson is the retired curator of the herbarium in the Department of Biological Sciences at the University of South Carolina. As a public service, the Herbarium offers free plant identifications. For more information, visit herbarium.org or email johnbnelson@sc.rr.com.
