Posts Tagged ‘growing corn’

Anatomy of a Corn Plant

Hard to believe these huge corn plants were just tiny seeds only a few months ago.

If you’re like me, and you live in Iowa, chances are you take for granted all the corn fields around you.  Have you ever really considered what goes on from the time the seed corn is planted until it is harvested?  I know I never did, until recent years.  I mean, really, is it not absolutely amazing that one tiny little seed planted just three months ago is now around 8 feet tall and nearly mature?

Little baby corn plants just popping out of the soil.

Have you ever wondered how that happens?  I mean, it is simple biology, so here is your lesson for the day:

Corn seeds are planted in a row no more than 2 inches deep and spaced about 6 inches apart.  The rows are 30 inches away from each other.  Depending on the soil temperature, the corn sprout will emerge anywhere from 3 days to 2 weeks.  As the plant grows over the next several weeks, it will add leaves and begin to develop an ear until it puts out a tassel. The tassel is the bushy top of the corn plant.  At this same time the ear will put out its silk. Both the silk and the tassel are considered part of the flower.

Russell is pointing to the silk. It is called silk because it consists of silky strands that stick out of the top of the ear.

The tassel on top of the plant contains pollen to fertilize the silk, which forms kernels on the ear.

Tasseling and pollination are critical times in corn development.  The tassel contains pollen that must make it to the silk in order to fertilize the plant. Each strand of silk must “catch” a pollen grain from the tassel to form a kernel. So, the number of  pollen grains caught by the silk, equals the number of  kernels formed on an ear.  This determines the yield. Corn plants usually fertilize other corn plants in a field (the silk catches pollen from a different plant).

Russell helping me show a close-up of the tassel.

A corn plant will only release pollen under ideal conditions.  Usually only during a few hours of a day, for a few days.  It can’t be too wet or dry or too hot or cold.  That’s why farmers can be so nervous during the growing season.  So much of their income depends on circumstances out of their control!

After pollination, it is now time for the corn plant to begin forming kernels over the next couple months, called the grain fill period. The kernel goes through a few stages.  These stages are basically based on the moisture content, size, and starch content of the kernel.  Once the kernel is fully formed, and contains about 30 percent moisture, it is considered physiologically mature, or black-tipped.

After the corn is mature, it is essentially dead, and farmers now begin the waiting game for it to dry down.  Ideally, we like to harvest our corn once the kernels are below 20% moisture.  How long it takes for corn to dry varies wildly, but dry corn harvest will usually begin around the second week of October here in Iowa.

Tall green corn and a bright blue sky... a sight to behold for a country girl!

See, fascinating, huh?  This was a hard post to write, as it would be very easy for me to get way too technical.  There is a lot of research and science that goes into field corn production.  Thanks to genetic technology and other advances, today’s farmer feeds 155 people.  That number is double what it was in the 1970’s.  I wonder what farming will be like in another 40 years?


Feeding the Corn

My apologies, the pictures for this entry are not of our equipment, as I just didn't get a chance to get out and take any while we were sidedressing. But they are very similar to what we do to feed our corn. The round metal things are called coulters, they run between the rows of corn and open up a small slot in the ground for the nitrogen to flow into. The small white tubes are what the nitrogen flows through and then dribbles out of directly behind the coulter. The entire thing mounted on the back of the tractor is called a toolbar.

The corn has been growing fast around the farm lately.  A lot of rain, warm weather, and sunshine will do that.  Applying crop nutrients, such as nitrogen, helps us to help nature.  Giving corn an extra boost of food, creates more yield per acre and increases our efficiency.  This allows the consumer to enjoy cheap food prices in the grocery store.  Did you know that the percentage of  income that Americans spend on food has shrunk from 23% to 9.5% since 1929?

There are many ways to fertilize corn.  Anhydrous,  dry urea, or manure are common forms.  We prefer to use liquid 28% nitrogen.  The 28 is kept in big tanks on the tractor, it flows through hoses and is dribbled near the row, right where the corn can take advantage of it.  The rate at which the fertilizer is applied can be controlled based on the variety of corn, and the fertility of the soil.  Often, if a field has had manure applied to it, it makes it unnecessary to apply additional nitrogen, or at the very lease, it reduces the rate needed.  Another way we reduce the amount of nitrogen needed is to plant soybeans.  The beans will “fix” nitrogen in the soil and make it available to the corn that is planted in their place next year.

A better view of the coulter and fertilizer delivery system.

We work closely with our agronomist to determine how much nitrogen to give to the corn.  It is costly, but when applied properly, will benefit the amount of corn we get from an acre.  Half of what the corn needs will be applied when the corn is planted.  The other half gets applied when the corn is around ankle to knee-high.

After we apply fertilizer, it’s pretty much up to mother nature to make the corn grow.  Soon after the corn gets it’s nitrogen, it will grow big enough to shade the soil between the rows and prevent any more weeds from growing.  The corn truly becomes at the mercy of the weather until it’s harvest time.

Just like I make sure my kids are getting the right nutrients to grow, I also make sure the corn is getting what it needs to be productive. (Oh, and yes, the kids are getting over pink eye in this picture)

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