Corn does have a flower, though it is not a typical blossom found on other plants. Corn (Zea mays) is a monocot and a member of the grass family. It is monoecious, meaning it produces separate male and female flowers on the same plant structure. This reproductive setup separates the pollen-producing organs from the ovule-containing organs, resulting in the tassel (male) and the ear (female).
The Male Flower: The Tassel
The tassel is the male flower cluster, or inflorescence, that develops prominently at the top of the corn stalk. This structure is easily recognizable by its branching, feather-like appearance, which stands above the foliage. The primary function of the tassel is to produce and release the pollen necessary for fertilization, acting as the male reproductive unit.
Within the tassel, smaller structures called spikelet flowers contain the anthers, which are the sacs that hold the pollen. A single tassel is capable of producing between two and five million grains of pollen. This large quantity ensures the success of the wind-driven pollination process.
The anthers open and shed their dust-like pollen. This process of pollen release, or “pollen shed,” typically begins two to three days before the female flowers are fully receptive. The shedding often starts at the center spike and continues outward and downward over a period of five to eight days, ensuring a sustained supply of genetic material.
The Female Flower: The Ear and Silk
The ear of corn, which develops lower down on the stalk at a leaf junction, serves as the female flower cluster. This structure is essentially a specialized inflorescence that holds the ovules, which will eventually become the kernels. The entire ear is protected by tightly wrapped, modified leaves called the husk.
Each potential kernel on the cob is an individual ovule, and each ovule has a single, hair-like extension called a silk. The silk is the combination of the stigma and the style of the female flower, botanically known as the pistil in other plants. Every strand of silk emerging from the top of the husk is directly connected to one ovule on the cob.
Every silk strand must capture a pollen grain. The silks are naturally sticky and moist to be receptive to the airborne pollen. Silk elongation begins first at the base of the ear and proceeds toward the tip, meaning the silks from the butt of the ear emerge from the husk first, followed by the tip silks over a period of about four to eight days.
The Pollination Process
Corn reproduction relies almost entirely on wind for moving the pollen from the male tassel to the female silks, a process called anemophily. The pollen grains, which are relatively heavy, fall from the tassel at the top of the plant and drift downward, often landing on the silks of the same plant or, more commonly, on a neighboring plant. Due to the weight of the pollen, most of it travels less than 50 feet.
When a pollen grain lands on the receptive, exposed silk, it germinates almost immediately. The pollen then grows a tube that travels down the length of the silk strand, which can be several inches long, to reach the ovule at the base. This journey culminates in fertilization, which generally happens within 12 to 24 hours of the pollen landing.
Once the ovule is fertilized, the silk connected to it stops elongating and begins to dry out, turning brown. The fertilized ovule then develops into the kernel, which is botanically the fruit and seed of the corn plant. A successful window of synchronized pollen shed and silk emergence is necessary to ensure that the 400 to 600 ovules on a typical ear are all fertilized.