Grass measuring is common practice on many dairy, beef and sheep farms, but on others it is not.

The spring-calving season is upon us, with input costs at an all time high. Farmers should now look at managing their grass better.

Grass measuring

Grazed grass is king on Irish farms. It is the focus on nearly every grassland farm and is used to market our products.

To offset some of the increasing costs on farms, grass should be maximised in our livestock’s diet.

The best way to maximise grass in the diet is to measure it. This will allow you to manage it better and achieve better production from animals.

From meeting farmers during the year, nearly all of them said that they have seen better production from their cows by simply measuring and managing their grass better.

Furthermore, the gains made in production will offset the investment needed in equipment quite quickly.

With chemical fertiliser prices being so high, slurry will also play an important role on farms this year. Monitoring grass growth will help to identify paddocks that require fertiliser and paddocks where slurry is needed.


There are two main methods used for measuring grass on farms.

The first is using a plate meter; using the plate meter, a farmer will make a number of drops in a paddock – this is usually done in an ‘X’ or ‘W’ pattern.

The farmer will then take the post-grazing height – or residual – from the average height of grass in the paddock; this figure should then be multiplied by 250kg of dry matter (DM), as there is 250kg of DM in 1cm.

The second option to farmers is the cut and weigh method. For this, a farmer needs a quadrant, shears, a plastic bag and a scale.

The quadrant should be placed in an area that is representative of the paddock. The grass is then cut to a high of 4cm using the shears.

The grass is then collected and weighed and a simple calculation is then used to determine the paddock’s cover.