Many esrogim do not have a pitam (the protuberance at the top of the citron).
To some this may seem a little strange, because they have been taught that an esrog must have a pitam. In truth, esrogim can be perfectly kosher even without the pitam. All fruit (oranges, apples, pears and esrogim) start out with a pitam. The pitam is the remnant of the female part of the flower. Once fertilized the pitam is no longer needed and, in almost every kind of fruit, it withers away. The esrog is unique in that in many cases it remains. Because of the demand for pitams, commercially produced esrogim are often sprayed with an artificial plant hormone to preserve the pitam.
If the pitam falls off naturally during growth, the esrog is still 100% kosher. If it instead breaks off, then the esrog is not kosher; it is easy to tell the difference between one that has fallen off naturally and one that has broken off. Accordingly, a pitamless esrog is favored by many people because there is no concern that their precious esrog will become posul (not kosher) sometime before or during Sukkot.
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