Back What makes a good maize silage crop?

Date: 18 March 2016

Maize silage harvest is currently underway in most regions of the country. Most of the costs associated with growing a maize crop are fixed, so the higher the yield per hectare, the lower the drymatter cost and the greater the potential return from your maize silage crop. There are some bumper crops this year, but also some paddocks where farmers have lost yield potential for a number of reasons. These include:

Hybrid choice.

It seems obvious that choosing a high yielding hybrid is one of the first steps in ensuring a high yielding maize silage crop, yet every season I run into a handful of farmers who are prepared to sacrifice yield to get cheap maize seed. At a $4.25 payout, assuming a milksolids response of 80 g/kgDM fed, it adds up to pay an extra $100 per hectare (including seed treatment) for a hybrid which will deliver you just 295 kg more drymatter yield. A hybrid which delivers 500 kg more drymatter is worth $170 per hectare more.

Seed quality.

Not all bags of maize seed are created equal. There are significant differences in the quality of maize being sold on the New Zealand market. Seed which has poor germination and/or vigour will result in uneven stands with lower than ideal plant populations. An optimal plant population is critical to ensuring high maize silage yields.

Genetic purity.

Hybrid maize seed is produced by crossing two purebred parent lines. Planted in an even paddock, genetically pure hybrid seed will produce plants which all look the same and have the same yield potential. This season we have seen plenty of non-Pioneer crops which have poor genetic purity. Plants are variable in height and flowered at slightly different times. This impacts silage yield, grain yield and even harvest timing. Always look for a hybrid which delivers an even plant stand as it’s critical to achieving high and consistent yields.

Image 1: A non-Pioneer crop showing the impact of poor genetic purity.     

Image 2: A Pioneer hybrid showing an even plant stand and good genetic purity.

Weed control.

Weeds compete with maize plants for sunlight, nutrients and water. Weedy crops produce less and the impact is even more marked in moisture-limited environments. The good news is there are a wide range of herbicides for controlling weeds in maize. If you are planting your paddock in maize silage again next season, spray it out with glyphosate prior to planting your winter pasture or crop. For paddocks coming out of pasture in the spring implement a good pre-emergent weed control program. Walk your crop regularly in the first few weeks after planting and be prepared to apply post-emergent herbicides where necessary.

As your maize comes off this autumn take a look at the crop and see if there are ways you can improve management to get an even higher yielding maize crop in 2017. Remember more yield means lower cost drymatter and higher returns. For more information on how you can get the most out of your maize investment next season, contact your local Pioneer representative