by Jordan Molloy Grassland Consultant
Recently, I was on a farm walk in Cork with farmers who have heavy farms. With the dry weather we have been getting lately, they have noticed the soil starting to dry out. This drought weather can cause problems. The farms still have growth rates of >70kg DM/ha for the moment but that could change quickly.
It all depends how close you are to a drought and how severe you think that drought will be. When entering a potential drought, I would advise farmers not to bale out or top paddocks. The paddocks may take longer than usual to come back and you may need to graze that grass. Also, the paddocks that have just been grazed may be affected by the drought and take longer to come back. Once you notice your growth rates starting to drop, keeping your cover/cow and AFC at the higher end will help keep grass in front of the cows.
Cover/cow target in the main grazing season is 140-190kg DM and AFC around 600-750kg DM/ha; keep them at the higher end. Grazing heavier paddocks will slow down your rotation and help you build covers.
Worst case scenario is when growth rates drop below demand. This leaves little options. If the drought is short, farmers may get away with sticking to their current feeding regime. If not, a reduction of grass in the diet is necessary by increasing meal and/or feeding silage.
When measuring grass, dry matter during dry periods will increase above 17%. In drought conditions, they can be between 19-24% and higher if in a severe drought.
Jordan Molloy – Grazing Consultant, Grasstec
“I teach farmers how to measure grass and the discipline needed to do weekly farm walks. I show them how to input their data onto Agrinet and how to understand the grass wedge. Each week presents a different scenario on the farm so it’s crucial that the farmer can interpret the data in order to make informed decisions. Grasstec consultants are available in Ireland and the UK.”