Like many other plants, sunflowers originated in North America and were first introduced to the European civilizations around the 16th century, by way of the Spanish conquistadors. For a long time before that, by some estimations as far back as 3,000 BC, they were cultivated by the native tribes across the continent for multiple purposes. Not only are their seeds a durable and nutritious food source, but they can also be used to make dye, oil or medicine. The Cherokee were known to make an infusion of sunflower leaves to threat kidney problems, while the Dakota tribe used it to sooth chest pains. Their oil is believed to have anti-inflammatory properties. Sunflowers have always captivated the human interest due to their peculiar behavior, called heliotropism. Each morning flower buds and young blossoms will meet the sunrise facing east and then throughout the day follow the path of the Sun, until it finally sets in the west. Mature blossoms however are usually too heavy with seeds and will spend their days remaining eastward.
The head of a sunflower is quite special. It is what scientists call a pseudanthium, which is Greek for “false flower”. Instead of one blossom, it is actually made up of thousands of smaller flowers. Even the petals themselves are individual flowers. The blossoms on the face of the flower, which later become the seeds, are arranged in a unique pattern, often encountered in nature. They form two spirals, winding around each other in opposite directions. For this to function, each seed must be aligned at a precise angle to its neighbor, at exactly 137.5 degrees. A variation of even a tenth of a degree can completely destroy the pattern. This angle is known as the Golden Ratio and it is closely tied to the Fibonacci sequence – a series of numbers, where each number is the sum of the previous two – 1, 2, 3, 5, 8, 13, 21 … By dividing two neighboring numbers we get a series of fractions: 2/3, 3/5, 5/8, 8/13 …, which over time approximate this angle precisely.
However, the sunflower’s most extraordinary property is probably their ability to extract radiation from contaminated soil. They were used back in the 80s at Chernobyl and are in use today at Fukushima in Japan. The way they do this is by extracting certain radioactive isotopes, which closely resemble the nutrients they usually need, like potassium and calcium. At the sites of nuclear explosions or accidents, the contamination is mostly airborne, but after a while the radioactive materials fall to the ground. There they rest in the top layers of the soil and have to be removed before the ground can again be deemed safe and usable. One way to do this is by simply removing the upmost layers of soil, but that is a very slow and costly process and it requires a place to store thousands of tons of polluted earth.
Fortunately, there is a much better way, one provided by nature. Some plants are able to extract these dangerous elements and can be then harvested and disposed of. The two main radioactive materials are strontium and cesium. Strontium has a form, similar to calcium, which is easily accessible to plants, but cesium is much more challenging. At an atomic level the soil is filled with many small cavities, where potassium is usually found. Cesium’s close resemblance to it allows it to also fit in there and becomes firmly fixed to the soil. That’s why plants, which suck up those two materials are ideal for cleaning up the earth. Field mustard, amaranth, cockscomb and most of all sunflowers. Because they build up biomass quickly and store it in their leaves and stems, they are perfect candidates. The radiation within the flowers is then much more concentrated than previously in the soil, making it easier to be gathered. After about three weeks they are harvested, so that they do not seed and become a hazard to birds, after which are burned, and the ashes stored as nuclear waste. This way an entire field can be cleared in just three years after the first planting.
You don't wanna miss new facts and stay updated? Enter your email-adress and get a monthly summary and be the first to get the latest news from AnnaDoYouKnow
We want to grow as a community, where we can discuss with and learn from each other. The more people we are, the more knowledge we have together. So if you have a friend, who would like our content and be interested in our facts, feel free to share.
It really helps and motivates us to keep going.
If you like our posts and concept, it really helps us when you share your thoughts and experiences - write a comment or send us a message. And if you want us to keep going, leave us a follow. If you have any suggestions, give us your feedback.
We'd love to hear from you!
We want to present you the best high quality facts and we put a lot of love and effort into our project. Each of us spends a lot of time preparing our posts, beside our regular jobs. So if you like our work and want to support us in a financial way (and buy Mietzi some treats ) you can do this here.
You can donate a single amount or subscribe monthly using the checkbox