Four leaf clovers

The four-leaf clover is a rare variation of the common three-leaf clover. According to tradition, such clovers bring good luck, though it is not clear when or how that tradition got started. The earliest mention of “Fower-leafed or purple grasse” is from 1640 and simply says that it was kept in gardens because it was “good for the purples in children or others”. A description from 1869 says that four-leaf clovers were “gathered at night-time during the full moon by sorceresses, who mixed it with Vervain and other ingredients, while young girls in search of a token of perfect happiness made quest of the plant by day”. The first reference to luck might be from an 11-year-old girl, who wrote in an 1877 letter to St. Nicholas Magazine, “Did the fairies ever whisper in your ear, that a four-leaf clover brought good luck to the finder?”

It is claimed that there are approximately 10,000 three-leaf clovers for every four-leaf clover. However, an actual survey of over 5 million clovers found the real frequency to be closer to 5000 to 1.

Even so, this probability has not deterred collectors who have reached records as high as 160,000 four-leaf clovers in a lifetime. However, the world record for four-leaf clovers in a single day is 72, and the record for one hour is 51, set by an American named Griffin McDowell on August 12, 2013.

Clovers can have more than four leaves. Five-leaf clovers are less commonly found naturally than four-leaf clovers; however, they, too, have been successfully cultivated. Some four-leaf clover collectors, particularly in Ireland, regard the five-leaf clover, known as a rose clover, as a particular prize. In exceptionally rare cases, clovers are able to grow with six leaves and more in nature. The most leaves ever found on a single clover stem (Trifolium repens L.) is 56 and was discovered by Shigeo Obara of Hanamaki City, Iwate, Japan, on 10 May 2009.

It is debated whether the fourth leaf is caused genetically or environmentally. Its relative rarity (1 in 5000 clovers) suggests a possible recessive gene appearing at a low frequency. Alternatively, four-leaf clovers could be caused by somatic mutation or a developmental error of environmental causes. They could also be caused by the interaction of several genes that happen to segregate in the individual plant. It is possible all four explanations could apply to individual cases. This means that multiple four-leaf clovers could be found in the same clover plant.

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Wikipedia