Saint Patrick might have used the leaves of a clover as a metaphor for the Holy Trinity, but today's shamrocks more commonly associated with good luck. And instead of combing through fields of clover in hopeless pursuit of a four- rather than three-leafed clover, you can up your odds with a scientific methodology.
As Scientific American explains, around one out of 10,000 clovers have four leaves. Around 200 clovers can be found in a 60-square centimeter plot of clover-growing grass or field, which means, on average, a space of about 1.2-square meters should contain a four-leaf clover.
The short version: when scanning that patch, don't examine every one of those 10,000 leaves. Instead, stare at the patch without focusing on any one detail. This increases the odds that a four-leafer—which deviates from the overall pattern of leaves—will jump out at you.