Make corn planting less stressful by doing as much preparation as possible ahead of time. This includes ensuring all equipment is in proper working order to prevent any problems. There are four main components in any corn planter that should be examined before planting.
1. Seed transmission system
Sprockets and chains should be in good condition. Sprockets should have no missing teeth and chains should be the correct tightness.
2. Opening disc
The opening disc should not be overly worn, and should be a minimum of 14.5″ in diameter to ensure the correct amount of contact at the bottom. Bottom contact depends on the make of the planter, but is generally in the 1.5 to 2.5″ range.
3. Bar height
Bar height should be equal to make sure the machine is level. Measurements should be taken from a number of points on the planter to ensure the planter is level. It is very important to level your planter in the field in motion and not in your shop.
4. Seed tubes
Any worn components of the seed tube should be replaced. A worn seed tube can affect how the seed drops which in turn affects the crop growth and emergence.
Consistent depth and spacing when planting is crucial to a successful season. If any component of the planter is out of order, it could affect how deep seeds are placed and spacing between plants, as well as overall yields of the crop. Even if you have purchased a new planter from an equipment dealer you need to be aware that they are not field ready, you still need to spend time setting the planter and checking all the above components.
Watch the environment too
In addition to well-tuned equipment, environmental factors impact planting. When planting takes place, it’s important that soil conditions are correct. Ideally, soil should not be too wet or dry. Corn should be planted 1.5 to 2.0″ deep; shallow planting will impede proper root development.
Soil temperature should be at least 10 C to prevent hormone problems in the seed, also known as imbibitional chill.
When the dry seed imbibes cold water as a result of a cold rain or melting snow, imbibitional chilling injury may result. The cell membranes of the seed lack fluidity at low temperatures, and under these conditions, the hydration process can result in rupture of the membranes. If the cell tissues of the kernel are too cold, they become less elastic and may rupture during the swelling process. Instances of chilling injury following germination during the emergence process can also occur, often causing stunting or death of the seminal root system, deformed elongation of the mesocotyl and either delayed emergence or complete failure of emergence.
This results in incorrect development of the plant and a decreased stand. Watch the weather forecast two to four days after planting to watch for cool temperatures.
Weed management is also an important consideration when planting corn. Growers need to be aware of what weeds they have in their fields and then develop a plan to manage those weeds. In corn, the yield opportunity is maximized if the corn is weed-free from spike/emergence to the V6 stage (approximately eight-leaf).
Well-maintained, properly tuned equipment and a strategy for planting can go a long way in reducing stress during a busy time. Take the time before planting to prepare and maintain controllable factors during a frenzied time and reap the rewards.
Nicole Rasmussen is an area agronomist with DuPont Pioneer