Agronomy Update: Let's Talk About Spring Planting

KEY REMINDERS FOR PLANTING CORN

Planting Depth: Plant 1.5-2 inches deep. Planting less than 1.5 inches deep, depending on weather and soil conditions, increases the probability of the corn seed not germinating, due to cooler soil temperatures or fluctuations in moisture in the seed zone.

Corn plants take in 30 percent of their weight in water during the germination process. By not having the proper planting depth you risk seeds not fully germinating or not having enough moisture to continue to grow. Another forgotten reason to plant 1.5 inches or deeper, is that many herbicide labels state that to safely use that product, corn needs to be planted 1.5 inches or deeper, or injury may occur.

Soil Temperatures: Plant when soil temperatures are 50°F or more, or when air and soil temperatures will be increasing to that level or more. Corn can germinate with temperatures less than 50°F, however germination is more consistent at 50°F or more. If soil temperatures are in the low 40°F or less, you can increase the incidence of Imbibitional Chilling Injury or Cold Shock Syndrome, which can kill plants and subsequently reduce plant populations/harvestable ears. Cool wet soils, increase the incidence of crown rot, as well as seedling diseases.

Starter: I recommend utilizing a quality liquid starter and zinc, to help the plant have an energy source (Phosphorus in the starter) and the ability to help move nutrients and protect the germination process (Zinc). It has been my experience that quality starter and zinc, helps the corn “Pop Up” out of the soil, and have better early season growth. It is also my observation that this early season growth translates to earlier Tassel and Pollination, which in most cases leads to increased yields, better test weight and dry down.

Plant Populations: My typical recommendation is to plant 1000-1500 more seeds than what is desired for a harvestable stand. Part of this is that not every seed will germinate, as well as:
• Less than ideal planting seedbed
• Hail/Greensnap
• Wildlife i.e. racoons, skunks, geese, turkeys, deer, grazing cattle and in some southern states wild hogs may eat seeds or seedlings
• Seed and Seedling diseases
• Soil Types

The ability to variable rate plant has changed how we handle some of these issues. This is a tool that provides a better Return on Investment rather than increasing the seeding rate across the entire field. If you have questions or concerns regarding this please contact your Dairyland Seed Representative or Agronomist.

ALFALFA

The Dairyland Seed Agronomy Team pretty well agrees – it was a miserable winter for alfalfa. Frost heaving and general winterkill (largely wet soils and very cold conditions, often with little or no snow cover) are taking a toll on alfalfa stands throughout the Dairyland Seed footprint. Now is the time to assess stands and make decisions for best production options.

In general, 2018 seedings (spring or fall) seemed to have fared the best. In some cases, these stands are okay and, in other instances, can be “thickened up”, perhaps best by no-tilling alfalfa into the existing thin stand.

Older, established seedings were generally hit harder by the harsh winter conditions and winter kill is, in many cases, severe enough to require terminating the alfalfa stand.

As you examine stands, here are a few thoughts:
• Minimum acceptable stands (more than one year old) are about 4 crowns per square foot and/or 40 stems per square foot. If you average less than that across the field, you will likely not have acceptable yield levels and you should likely remove that stand.
• Frost – heaving – crowns that have “heaved” up 2-3 inches or more often have a severed tap root and will likely never produce well.
• Dig a few crowns and cut or tear from the top to examine root health. White or yellow-white color generally indicates pretty good root health. Brown or black and/or woody root tissue is likely an indication of disease and likely future demise of that plant.

If you find that your stand is not adequate or healthy enough to keep, what are your alternatives? You may be able to interseed some grass (Italian ryegrass or oats, for example) to get some mixed forage. In general, I prefer to rotate out of alfalfa and plant corn (for silage if needed) or maybe an emergency summer forage such as sorghum sudangrass. Interseeding a grass into a poor alfalfa stand often does not work well due to competition challenges from the remaining alfalfa and weed issues.

There are many other factors to consider. Dairyland Seed is well aware of the widespread issues around alfalfa winterkill, and is ready to assist you in stand assessment and in a seed program to reestablish alfalfa to best manage your forage needs. Call your Regional Agronomist or District Sales Manager to let us know how we can assist.

WHEAT STAND ASSESSMENT

For those you who grow wheat……it was a brutal fall to get wheat established and the winter conditions were generally not favorable. Thus, we are now looking at a lot of wheat stands that are questionable at best. If you are wondering whether or not to keep your wheat, call us – we’ll be happy to walk fields with you to assess stand viability/yield potential and to discuss options.