Near-infrared spectroscopy (NIRS) is at the heart of numerous new technologies, all designed to help farmers and contractors secure accurate and real time information as they operate in the field and while formulating forage-based livestock rations.

This was the key message communicated at a grassland management webinar hosted by John Deere UK this week. The event was supported by Meath Farm Machinery.

NIRS is now an integral part of numerous analysis and control systems, all designed to allow their operators make real time decisions that can impact positively where silage making and feeding operations are concerned.

In the field, they can deliver continuous information on forage dry matter, ME (metabolisable energy) values plus forage sugar and energy levels.

NIRS consequences

Two practical consequences are the linked ability to alter chop length, depending on forage dry matter, and to tweak inoculant application rates in line with sugar levels. Again, all these changes can be made automatically and in real time as the forage harvester is operating.

NIRS can also be used to assess the nutritional values of all the dietary components included in a TMR, each time a feed is made up.

Information of this nature can allow the farmer, or farm manager, to tweak ration specification, in the moment, with the aim of saving cost or increasing production levels.

Nutrient value of slurry

The third use to which NIRS can be put is that of analysing the nutrient value of slurry – again on a real time basis – as it is spread using a dribble bar or trailing shoe system.

Research has shown that slurry is not a homogenous product. Fertiliser values can vary within a specific store and even within a single tanker load.

By combining the results generated by previous yield maps and the use of a NIRS system – linked to a variable rate slurry applicator – the farmer / contractor can specifically apply the requisite amount of slurry at each point within a field.

By taking this approach, best use can be made of what constitutes an extremely valuable resource on all livestock farms.


John Deere’s offering within this sector is HarvestLab 3000. While in the field, it provides on-the-go measurements of moisture; dry matter; protein; starch; fibre; neutral detergent fibre; acid detergent fibre; and sugar levels within the grass or forage being harvested..

The system will automatically adjust inoculant dosage rates, based on forage dry matter levels, while also changing chop length, in order to ensure optimal consolidation of the silage clamp.

Extensive trials in the UK have confirmed that the system can be used to drive the efficient use of variable rate slurry application systems.