Plant counts are a very useful task to carry out. At this time of the year – and in a season like this – when crops are struggling plant counts can be a help in making agronomic decisions.

Those decisions may include whether or not the crop needs to be replanted or if farmers need to reduce inputs.

In this short video, AgriLand describes how to carry out a plant count.

The main points to note are:

  • Take a representative sample – in different areas of the field;
  • Use a ruler or an apparatus such as a quadrat which you know the size of and can multiply out to get 1m²;
  • If using a ruler or measuring tape:
    • Count the number of rows across 1m – this will vary between seed drills;
    • Count the number of plants along 50cm in a row;
    • Multiply this number by 2 and again by the number of plants across 1m to give the number of plants/m²;
  • This process should be carried out numerous times in different locations.

Winter wheat crops which have 90 plants/m² are considered viable. Winter wheat crops have a good ability to compensate.

However, looking at winter barley and approximately 1,200 tillers are needed for a crop to be viable. As outlined in the video, tiller numbers should be recorded when carrying out a plant count. The number of plants can then be multiplied by the average number of tillers to calculate the tiller numbers/m².

Where numbers are low farmers should adjust management decisions accordingly. For example, nitrogen rates may be reduced or a plant growth regulator may be applied.

This ‘How to video’ aired first on FarmLand. The newest episode of FarmLand is available today, Thursday, March 19, from 5:30pm.

On this week’s episode, we go through how to calibrate a seed drill. Michael Moroney will talk about the carbon tax increase and Kilcullen Mart celebrates a milestone anniversary.