Fall Armyworm in NZ Maize: Four Years of Research
Four years since it was first detected in New Zealand, researchers and growers now know much more about management of maize pest fall armyworm (FAW).
From flag leaf through to cheesy-dough grain stage, May-sown plots of wheat, oats, barley and triticale at Lincoln averaged 310kgDM/ha/day growth last spring.
“The triticale was the highest yielding but maybe not the best quality and the wheats were right up there with it,” pointed out FAR researcher Elin Arnaudin during a recent Results Round Up meeting.
Yields across all species were 20-23tDM/ha at the cheesy dough stage, reached in mid-late December. That compares to just 4-5tDM/ha when taken as greenchop at the flag-leaf to booting stage of the crop in late October to early November, she pointed out.
With such stellar growth rates, every day in the paddock means a much bigger stack come harvest, but Arnaudin stressed the 30-46% drymatter window for ensiling mustn’t be missed.
Plant growth regulators reduced yield overall but did increase the percentage grain content of taller wheat cultivars, suggesting a feed quality benefit.
Wholecrop cereal silage taken at the cheesy dough stage is a high carbohydrate, low protein feed suitable for supplementing pasture which would “hopefully” be worth 25c/kgDM, said Arnaudin. Green-chopped crop has a higher protein, lower fibre and starch content.
Taking cereals as wholecrop can reduce growing costs compared to grain and means the paddock is cleared earlier for following crops.
