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Selecting the right corn silage hybrid

Mark Schultz Published on 31 December 2010
For dairy farmers, selecting the right seed for corn silage is essential for efficient, profitable milk production. Most dairy farmers are working with a finite number of acres, so it is crucial those acres generate the greatest value of high-quality corn silage. After all, on a dairy farm, an acre of ground is not for making silage; it is for making milk.

Selecting corn hybrids may seem overwhelming, as producers must consider many factors to make the best choice for their acres. Accomplishing this task requires thoughtful planning, careful execution and some cooperation from nature. Below are several steps to help guide you in choosing the right corn silage hybrid.

Consider the past
Before you begin to dive into the various hybrids available, you should take a step back and look at the history and performance of your crop over the past several years. Additionally, consider weather and environmental patterns in a given area, as these can affect the maturity of a crop and often vary from year to year. These factors can also help determine the appropriate harvest maturity as well as necessary input traits.

Then, look at results from multiple plots and other sources of yield data to see how a particular hybrid has performed over the years. You might consider looking at data from seed companies, universities and extension specialists. Be sure to look at several years worth of data so you can analyze trends. Additionally, it’s best to look at data from your area or a similar geography to get an idea of how a hybrid might behave in your situation.

Armed with this historical background, you’re ready to start narrowing down corn silage hybrid choices.

Select the right seed genetics
Concentrate on hybrids that are specifically designed for silage, such as NutriDense® Silage. Dual-purpose or grain hybrids can be chopped for silage, but for the best possible quality, it is better to choose a hybrid designed with the dairy cow in mind. Consult with your nutritionist to determine the needs of the ration and the nutritional objectives of the year ahead.

You must also take into consideration relative maturity (RM). Often referred to as “day rating,” a hybrid’s RM is the length of time it takes for a hybrid to reach maturity, and is expressed as a number. Each seed company will assign an RM value to their hybrids to describe the seed’s maturity, and one must pay particular attention to the RM value or number when selecting a silage hybrid. Some companies will list a silage RM with a different value than the grain RM since the silage crop never actually reaches physiological maturity. Typically, producers will use the longest RM hybrids that are practical for a given region to take full advantage of the growing season. For example, producers growing corn silage in the northern Corn Belt will need to select a hybrid with a shorter RM to accommodate the shorter growing season.

Choose input traits wisely
While maturity is important, it’s only one piece of the puzzle. Achieving a good crop also involves choosing hybrids with the right input traits, such as herbicide and pest resistance.

Competition from uncontrolled weeds can have a devastating effect on corn grown for silage. Weeds compete for water and nutrients, and this competition can cause corn plants to be stunted, possibly reducing the size of the developing ear. Biotechnology and the use of herbicide-resistant corn have allowed successful weed control to be easier and more cost-effective. When selecting a silage hybrid, consider whether traits such as Roundup Ready® Corn 2 or Liberty Link® make sense for your operation.

In addition to herbicide-resistant traits, producers should consider hybrids that have insect-resistant traits. Some corn hybrids have been genetically modified to produce a specific bacillus thuringiensis (Bt) protein that is extremely effective at controlling certain lepidopteron insect pests. European corn borer, northern corn rootworm and western corn rootworm have historically done the most damage to corn, and are therefore most commonly targeted by a Bt trait. Some Bt traits are also effective at controlling secondary insect pests such as black cutworm, armyworm and western bean cutworm.

Since the entire plant is harvested for silage, the negative consequences of stand reduction from insect pests are greater than for a corn crop grown for grain. Remember that refuge acres are required when planting Bt corn, and pest management for those acres should be managed accordingly.

Always look for quality
Finally, selecting a corn hybrid should be based on quality. Many seed companies are creating forage quality profiles of their corn hybrids. Silage hybrids should have high forage yields, high digestibility, low fiber levels and highly digestible stover. However, silage hybrid rankings may vary because of differences in fiber digestibility and grain-to-stover ratio. Be sure to consult a nutritionist as well as an agronomist when selecting corn silage hybrids to ensure you are covering all your bases.  FG

Mark Schultz
Sales Agronomist
BASF Plant Science