Nitrogen use efficiency in maize

Read the booklet for the 2025 autumn round up series here. 

Fall armyworm (Spodoptera frugiperda) is a highly invasive plant pest first detected in New Zealand in February 2022. Fall armyworm (FAW) larvae can feed on over 350 plant species and in New Zealand, the crops at most risk are sweetcorn and maize. This update outlines the pest's biology and behaviour and provides tips for identifying and managing fall armyworm in maize and sweet corn crops.

It was great to see 90 people at our NCRS maize field day last week. This day, along with a series of field events across the central North Island, introduced around 150 growers and industry reps to Jon Myhill and Kate Baker from the UK Maize growers Association. 

Booklet covers: UK maize; nitrogen management; changing the maize system; herbicide resistance and maize weeds, combine set up.

Weed related yield losses ranging from 15 % to 56 % for silage and 15 % to 61 % for grain have been observed in New Zealand maize systems. And with herbicide resistance being an ongoing challenge growers need to know if and when to spray to maintain herbicide effectiveness and manage input costs. This update discusses the results of a three-year AgResearch-FAR, post-emergence herbicide trial to evaluate the effects of various herbicide treatments on different weed species at both small and large growth stages.

FAR's technology manager Chris Smith gives you some tips and tricks to help you pick the best moisture sensor for your system.

In 2023, FAR set up a Moisture Monitoring project at its Kowhai Research Site in Lincoln to provide independent insights into the range of moisture monitoring systems available in New Zealand. This report covers findings from the first year of the trial and outlines key considerations when choosing a moisture monitoring system.

Pure Oil NZ and FAR are collaborating to monitor oilseed rape (OSR) paddocks to identify strategies to improve yields. Their work has identified that many growers could reduce the amount of nitrogen applied to OSR crops without impacting on yield or profit.

This Arable Extra discusses optimal nitrogen rates for crops based on 2024-25 fertiliser and crop prices.